Schedule of Expected Benefit Payments (Detail) $ in Thousands	Mar. 31, 2017 USD ($)
Pension Plans, Defined Benefit
Schedule of Pension Expected Future Benefit Payments [Line Items]
2018	$ 6,746
2019	6,931
2020	8,504
2021	7,358
2022	7,318
2023 – 2027	37,620
Total 10-year estimated future benefit payments	74,477
Other Pension Plans, Defined Benefit
Schedule of Pension Expected Future Benefit Payments [Line Items]
2018	418
2019	415
2020	429
2021	411
2022	404
2023 – 2027	1,765
Total 10-year estimated future benefit payments	$ 3,842