CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (JPY ¥) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Net income	¥ 53,111us-gaap_ProfitLoss	¥ 38,384us-gaap_ProfitLoss	¥ 74,388us-gaap_ProfitLoss	¥ 104,647us-gaap_ProfitLoss
Other comprehensive income (loss):
Change in cumulative translation adjustments, net of tax	58,079	(5,542)	46,285	27,431
Defined benefit pension plans:
Pension liability adjustment	14	449	374	2,005
Deferred income taxes	(69)	(171)	(211)	(703)
Total	(55)	278	163	1,302
Non-trading securities:
Net unrealized gain on non-trading securities	6,312	4,471	9,712	1,469
Deferred income taxes	(2,017)	(1,286)	(2,539)	(645)
Total	4,295	3,185	7,173	824
Total other comprehensive income (loss)	62,319	(2,079)	53,621	29,557
Comprehensive income	115,430	36,305	128,009	134,204
Less: Comprehensive income attributable to noncontrolling interests	3,574	962	5,380	1,382
Comprehensive income (loss) attributable to NHI shareholders	¥ 111,856us-gaap_ComprehensiveIncomeNetOfTax	¥ 35,343us-gaap_ComprehensiveIncomeNetOfTax	¥ 122,629us-gaap_ComprehensiveIncomeNetOfTax	¥ 132,822us-gaap_ComprehensiveIncomeNetOfTax

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The change in unrealized holding gain (loss), net of tax, on available-for-sale securities included in a separate component of shareholders' equity during the period.

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This item represents the tax effects occurring during the period which are related to the net unrealized gain (loss) resulting from changes in the fair [carrying] value during the period of available-for-sale securities. Such tax affects would have been charged or credited directly to other comprehensive income or to related components of shareholders' equity.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount of tax (expense) benefit, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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