Commitments, contingencies and guarantees (Tables)

12 Months Ended

Mar. 31, 2020

Commitments, Contingencies and Guarantees [Abstract]

Commitments outstanding

	Millions of yen
	March 31, 2019		March 31, 2020
Commitments to extend credit
Liquidity facilities to central clearing counterparties	¥	1,593,439	¥	1,288,774
Other commitments to extend credit		1,100,929		958,659
Total	¥	2,694,368	¥	2,247,433
Commitments to invest	¥	14,413	¥	15,278

Maturity schedule of commitments

	Millions of yen
	Total contractual amount		Years to maturity
			Less than 1 year		1 to 3 years		3 to 5 years		More than 5 years
Commitments to extend credit
Liquidity facilities to central clearing counterparties	¥	1,288,774	¥	1,288,774	¥	—	¥	—	¥	—
Other commitments to extend credit		958,659		110,312		139,295		167,322		541,730
Total	¥	2,247,433	¥	1,399,086	¥	139,295	¥	167,322	¥	541,730
Commitments to invest	¥	15,278	¥	491	¥	4	¥	5,628	¥	9,155

Maturity schedule of purchase obligations

	Millions of yen
	Total		Years of payment
			Less than 1 year		1 to 2 years		2 to 3 years		3 to 4 years		4 to 5 years		More than 5 years
Purchase obligations	¥	126,949	¥	20,523	¥	24,206	¥	11,514	¥	8,280	¥	112		¥62,314

Information on derivative contracts and standby letters of credit and other guarantees

	Millions of yen
	March 31
	2019				2020
	Carrying value		Maximum potential payout / Notional total		Carrying value		Maximum potential payout / Notional total
Derivative contracts(1)(2)	¥	4,315,743	¥	281,605,308	¥	7,197,647	¥	279,734,884
Standby letters of credit and other guarantees(3)		80		5,764		—		2,351

(1) Credit derivatives are disclosed in Note 3 “Derivative instruments and hedging activities” and are excluded from derivative contracts.

Maturity information on derivative contracts and standby letters of credit and other guarantees

	Millions of yen
	Carrying value		Maximum potential payout/Notional
			Total		Years to Maturity
					Less than 1 year		1 to 3 years		3 to 5 years		More than 5 years
Derivative contracts	¥	7,197,647	¥	279,734,884	¥	71,355,150	¥	77,870,884	¥	35,538,204	¥	94,970,646
Standby letters of credit and other guarantees		—		2,351		10		1,184		1,156		1