Employee Benefit Plans - Components of Postretirement Benefit Income and Pension Cost (Detail) (USD $)
In Thousands, unless otherwise specified |
3 Months Ended | 6 Months Ended | ||
---|---|---|---|---|
Sep. 30, 2013
|
Sep. 30, 2012
|
Sep. 30, 2013
|
Sep. 30, 2012
|
|
Pension Plans, Defined Benefit [Member]
|
||||
Defined Benefit Plan Disclosure [Line Items] | ||||
Service cost | $ 144 | $ 136 | $ 288 | $ 272 |
Interest cost | 339 | 356 | 679 | 713 |
Expected returns on assets | (682) | (685) | (1,364) | (1,369) |
Amortization of unrecognized prior service cost (benefit) | 1 | 1 | 2 | 2 |
Amortization of actuarial loss | 251 | 254 | 501 | 506 |
Net pension cost and postretirement benefit income | 53 | 62 | 106 | 124 |
Other Postretirement Benefit Plans [Member]
|
||||
Defined Benefit Plan Disclosure [Line Items] | ||||
Service cost | ||||
Interest cost | 8 | 10 | 16 | 19 |
Amortization of unrecognized prior service cost (benefit) | (42) | (42) | (83) | (83) |
Amortization of actuarial loss | 11 | 9 | 22 | 19 |
Net pension cost and postretirement benefit income | $ (23) | $ (23) | $ (45) | $ (45) |