Employee Retirement Plans (Periodic Service Costs) (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Change in benefit obligation:
Projected benefit obligation at beginning of period	$ 61,882	$ 61,714
Interest cost	2,380	2,529	$ 456
Actuarial (gain) loss	(744)	800
Benefits paid	(3,184)	(3,161)
Projected benefit obligations at end of year	60,334	61,882	61,714
Change in plan assets:
Fair value of plan assets at beginning of period	50,508	47,772
Actual return on plan assets	2,416	5,505
Employer contribution	1,375	392
Benefits paid	(3,184)	(3,161)
Fair value of plan assets at end of year	51,115	50,508	$ 47,772
Funded status at end of year	$ (9,219)	$ (11,374)

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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- Definition

Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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Amount of increase (decrease) in plan assets of defined benefit plan from assets transferred into (from) plan.

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No definition available.

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- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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- Definition

Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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