Retirement Plans - Schedule of Changes in Benefit Obligations and Plan Assets (Details) - Pension Plans, Defined Benefit - USD ($) $ in Millions	6 Months Ended
Sep. 30, 2018
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation as of April 1, 2018	$ 0
Service cost	0
Interest cost	0
Benefits paid	0
Obligation transferred in	6
Benefit obligation at end of the period	6
Defined Benefit Plan, Change in Plan Assets [Roll Forward]
Fair value of plan assets as of April 1, 2018	0
Company contributions	0
Benefits paid	0
Plan assets transferred in	0
Fair value of plan assets at end of the period	0
Funded status recognized in the balance sheet	$ (6)

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

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.

+ References

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- Definition

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.

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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- Definition

Amount of decrease in benefit obligation of defined benefit plan from disposal or classification as held-for-sale.

+ References

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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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- Definition

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

+ References

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- Definition

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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- Definition

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

+ References

+ Details

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