Income tax benefit recognized from net operating losses

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- Definition

Income Taxes [Line Items]

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- Definition

Amount after allocation of valuation allowances of noncurrent deferred tax asset attributable to deductible temporary differences and carryforwards. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences, netted by jurisdiction and classified as noncurrent.

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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- Definition

Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other deductions.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Expiration date of each operating loss carryforward included in operating loss carryforward, in CCYY-MM-DD format.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Income Taxes - Additional Information (Detail) - JPY (¥) ¥ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Income Taxes [Line Items]
Income tax benefit recognized from net operating losses	¥ 5,451	¥ 3,888	¥ 26,990
Domestic effective statutory tax rate	33.00%	36.00%	38.00%
Decrease in net deferred tax liabilities	¥ 1,525
Net deferred tax assets included in Other assets-Other	36,130	¥ 19,718
Net deferred tax liabilities included in Other liabilities	35,238	¥ 71,165
Undistributed earnings, No deferred tax provided	10,649
Operating loss carryforwards	2,127,536
Company and domestic subsidiaries \| Domestic
Income Taxes [Line Items]
Operating loss carryforwards	602,036
Subsidiaries [Member] \| United Kingdom
Income Taxes [Line Items]
Operating loss carryforwards	721,069
Subsidiaries [Member] \| United States
Income Taxes [Line Items]
Operating loss carryforwards	511,732
Subsidiaries [Member] \| Hong Kong
Income Taxes [Line Items]
Operating loss carryforwards	217,337
Subsidiaries [Member] \| Other tax jurisdictions
Income Taxes [Line Items]
Operating loss carryforwards	75,362
Indefinitely [Member]
Income Taxes [Line Items]
Operating loss carryforwards	1,009,812
Initial term [Member]
Income Taxes [Line Items]
Operating loss carryforwards	¥ 769,789
Expiration year	Mar. 31, 2025
Next term [Member]
Income Taxes [Line Items]
Operating loss carryforwards	¥ 347,935
Tax Year 2016 [Member]
Income Taxes [Line Items]
Domestic effective statutory tax rate	32.00%
Tax Year 2017 [Member]
Income Taxes [Line Items]
Domestic effective statutory tax rate	31.00%
Percentage of use of operating loss carryforwards as a deduction for tax purposes	60.00%
Tax Year 2018 [Member]
Income Taxes [Line Items]
Percentage of use of operating loss carryforwards as a deduction for tax purposes	55.00%
Tax Year 2019 [Member]
Income Taxes [Line Items]
Percentage of use of operating loss carryforwards as a deduction for tax purposes	50.00%