Income Taxes (Detailed Amounts of Tax Effects of Items Recorded Directly in Equity) (Detail) - JPY (¥) ¥ in Millions	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Net unrealized gains (losses) on available-for-sale securities:
Unrealized gains (losses)	¥ (10,012)	¥ (3,940)	¥ 123,186
Less: reclassification adjustments	(8,410)	889	(82,828)
Total	(18,422)	(3,051)	40,358
Pension liability adjustments:
Unrealized gains (losses)	(52,888)	(6,558)	66,331
Less: reclassification adjustments	(1,765)	(2,370)	190
Total	(54,653)	(8,928)	66,521
Own credit risk adjustments:
Unrealized gains (losses)	5,052	3,033	0
Less: reclassification adjustments	387	(47)	0
Total	5,439	2,986	0
Total tax effect before allocation to noncontrolling interests	¥ (67,636)	¥ (8,993)	¥ 106,879

The sum of the tax effects of all items occurring during the period that have been charged or credited directly to other comprehensive income or to related components of shareholders' equity.

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