Income Taxes (Unrecognized Tax Benefit) (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Income Tax Disclosure [Abstract] | |||
| Accrued penalties and interest (less than $1 million) | $ 1 | $ 0 | $ 1 |
| Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] | |||
| Beginning Balance | 12 | 13 | 11 |
| Increases related to tax positions taken during a prior period | 2 | 0 | 1 |
| Increases related to tax positions taken during the current period | 1 | 2 | 3 |
| Decreases related to settlements with taxing authorities | 0 | 0 | 0 |
| Decreases as a result of a lapse of the applicable statute of limitations | (2) | (2) | (1) |
| Decreases related to tax positions taken during a prior period | 0 | (1) | (1) |
| Ending Balance | $ 13 | $ 12 | $ 13 |
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
|
| X | ||||||||||
- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|