| Mar 31, 2013 | Mar 31, 2014 | Mar 31, 2015 | Mar 31, 2016 | Mar 31, 2017 | Mar 31, 2018 | Mar 31, 2019 | Mar 31, 2020 |
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| Profit (loss) before income taxes | 708 | 1,398 | 1,542 | 37 | -2,031 | 1,378 | 745 | 1,093 |
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| Depreciation | 1,932 | 2,076 | 2,775 | 1,834 | 757 | 440 | 480 | 547 |
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| Impairment loss | 164 | 373 | - | 12 | - | 61 | - | 7 |
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| Increase (decrease) in allowance for doubtful accounts | 63 | -38 | -190 | -33 | -49 | 3 | -23 | -3 |
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| Increase (decrease) in provision for bonuses | 112 | -2 | 37 | -9 | 12 | 10 | -20 | 27 |
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| Increase (decrease) in provision for bonuses for directors (and other officers) | 46 | 26 | -4 | -28 | -19 | 30 | -3 | 18 |
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| Increase (decrease) in retirement benefit liability | - | 64 | 26 | 113 | 114 | 86 | 100 | 89 |
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| Increase (decrease) in reserve for financial instruments transaction liabilities | -312 | 163 | 140 | 107 | -60 | - | -118 | -11 |
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| Interest and dividend income | -636 | -735 | -704 | -604 | -458 | -451 | -219 | -215 |
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| Interest expenses | 115 | 140 | 196 | 184 | 166 | 181 | 24 | 44 |
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| Loss (gain) on sales of non-current assets | - | - | -245 | -159 | -7 | - | -2 | - |
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| Loss on retirement of non-current assets | 4 | 8 | 7 | 2 | 2 | 15 | 8 | 15 |
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| Loss (gain) on valuation of investment securities | 4 | 203 | - | - | - | 31 | 36 | 12 |
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| Loss (gain) on sales of investment securities | -1 | -26 | -323 | -37 | - | -11 | - | 4 |
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| Decrease (increase) in cash segregated as deposits | -86 | -229 | -83 | -191 | -33 | -446 | -2,023 | 920 |
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| Decrease (increase) in operating loans receivable | -3,195 | 2,586 | 1,531 | 4,010 | 2,728 | 105 | 2,200 | 225 |
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| Decrease (increase) in margin transaction assets | -3,088 | 22 | -4,963 | 6,425 | -1,282 | 4,676 | -467 | 1,792 |
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| Decrease (increase) in operating accounts receivable | 569 | -451 | -164 | -171 | -158 | 572 | -655 | 100 |
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| Decrease (increase) in short-term guarantee deposits | -2,335 | -1,371 | -742 | 226 | -1,318 | 5,442 | -100 | 100 |
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| Increase (decrease) in margin transaction liabilities | 1,726 | -3,202 | 7,468 | -5,970 | 2,442 | -7,772 | 658 | -633 |
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| Increase (decrease) in borrowings secured by securities | -20 | -250 | - | 52 | 433 | -225 | 308 | 728 |
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| Increase (decrease) in operating accounts payable | -164 | 311 | -107 | 341 | -73 | -324 | 413 | -67 |
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| Increase (decrease) in short-term guarantee deposits received | 1,322 | 2,959 | 755 | 31 | -1,002 | -3,165 | 1,452 | -60 |
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| Other, net | 486 | -570 | -98 | -1,091 | -512 | 689 | -133 | 454 |
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| Subtotal | -1,835 | 4,040 | 6,608 | 5,421 | 2,389 | 1,806 | 2,806 | 5,430 |
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| Interest and dividends received | 697 | 711 | 694 | 620 | 429 | 483 | 208 | 221 |
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| Interest paid | -112 | -141 | -196 | -184 | -171 | -178 | -24 | -43 |
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| Income taxes (paid) refund | -214 | -579 | -583 | 65 | -437 | -39 | -121 | -247 |
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| Net cash provided by (used in) operating activities | -1,465 | 4,035 | 6,266 | 5,921 | 2,209 | 2,072 | 2,868 | 5,361 |
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| Payments into time deposits | - | - | - | - | - | -500 | -500 | -500 |
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| Proceeds from withdrawal of time deposits | - | - | - | - | - | - | 500 | 500 |
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| Decrease (increase) in deposits paid | - | - | - | - | - | - | - | 2,000 |
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| Purchase of securities | - | - | - | - | - | - | -2,007 | -2,707 |
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| Proceeds from redemption of securities | - | - | - | - | - | - | - | 2,400 |
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| Purchase of property, plant and equipment | -49 | -116 | -1,079 | -475 | -94 | -355 | -165 | -104 |
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| Proceeds from sales of property, plant and equipment | - | - | 1,408 | 5 | 25 | - | 4 | 2 |
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| Purchase of intangible assets | -766 | -2,085 | -3,244 | -4,869 | -663 | -403 | -332 | -493 |
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| Purchase of investment securities | -99 | -5 | - | - | - | -1 | -101 | - |
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| Proceeds from sales of investment securities | 201 | 265 | 1,274 | 248 | - | 39 | 7 | 32 |
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| Proceeds from sales of shares of subsidiaries resulting in change in scope of consolidation | - | - | - | - | - | - | 918 | - |
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| Other, net | -91 | -659 | 96 | 26 | -146 | -136 | -104 | -76 |
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| Net cash provided by (used in) investing activities | -1,712 | -2,391 | -1,658 | 1,806 | -879 | -2,212 | -1,780 | 1,052 |
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| Net increase (decrease) in short-term borrowings | 3,416 | 1,276 | 426 | -8,375 | - | 130 | 500 | - |
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| Repayments of long-term borrowings | - | - | -333 | -666 | - | -500 | -500 | - |
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| Purchase of treasury shares | - | - | - | - | - | -358 | - | -90 |
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| Proceeds from disposal of treasury shares | - | - | - | - | - | - | 71 | - |
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| Dividends paid | -380 | -382 | -381 | -382 | -294 | -203 | -276 | -251 |
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| Other, net | -7 | -9 | -9 | -11 | -8 | - | -2 | -5 |
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| Net cash provided by (used in) financing activities | 2,968 | 1,824 | -498 | -9,436 | -302 | -932 | -207 | -346 |
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| Net increase (decrease) in cash and cash equivalents | -206 | 3,468 | 4,109 | -1,708 | 1,027 | -1,072 | 880 | 6,067 |
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