Employee benefit plans (Tables)

6 Months Ended

Sep. 30, 2022

Employee Benefit Plans [Abstract]

Net periodic benefit cost for defined benefit plans

	Millions of yen
	Six months ended September 30
	2021			2022
Service cost	¥	3,226		¥	3,199
Interest cost		1,021			1,216
Expected return on plan assets		(3,028	)		(2,984	)
Amortization of net actuarial losses		1,978			1,909
Amortization of prior service cost		(800	)		(803	)
Net periodic benefit cost	¥	2,397		¥	2,537
	Millions of yen
	Three months ended September 30
	2021			2022
Service cost	¥	1,613		¥	1,600
Interest cost		510			608
Expected return on plan assets		(1,514	)		(1,492	)
Amortization of net actuarial losses		989			954
Amortization of prior service cost		(400	)		(401	)
Net periodic benefit cost	¥	1,198		¥	1,269