Employee Benefit Plans - Postretirement Plan (Details) - Postretirement Plan - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2021 |
Sep. 30, 2020 |
Sep. 30, 2021 |
Sep. 30, 2020 |
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| Defined Benefit Plan Disclosure [Line Items] | ||||
| Interest cost | $ 0 | $ 0 | $ 0 | $ 0 |
| Amortization of prior service benefit | 0 | (1) | 0 | (2) |
| Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) | (1) | (1) | (1) | (1) |
| Net periodic benefit cost (income) | 1 | $ 0 | 1 | $ (1) |
| Plan assets contributions by employer | $ 1 | $ 1 | ||
| X | ||||||||||
- 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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