v3.19.1

Defined Contribution and Defined Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Contribution and Defined Benefit Plans [Abstract]
Defined Contribution Plan, Cost	$ 20	$ 14	$ 11
Employer Matching Contribution Percentage	100.00%
Deferral Election Percentage For Employer Matching Contribution	5.00%
Employee Deferral Limit Percentage	75.00%
Defined Benefit Pension Plan, Percent of Eligible Participants	3.00%
Assets for Plan Benefits, Defined Benefit Plan	$ 19	21
Liability, Defined Benefit Plan	27	29
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position	8	8
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	1	1	$ 2
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax	4	5
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year	1	$ 2
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year	4
Defined Benefit Plan, Expected Future Benefit Payments in Five Fiscal Years Thereafter	$ 1

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Defined Benefit Pension Plan, Percent of Eligible Participants

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Defined Contribution and Defined Benefit Plans [Abstract]

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Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

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Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

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Amount of contributions expected to be received by defined benefit plan from employer in fiscal year. Excludes contributions paid by employer in current fiscal year.

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Amount of net periodic benefit cost (credit) for defined benefit plan.

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