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Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
U.S. Statutory Tax Rate		35.00%	35.00%	35.00%
Adjustment to deferred income tax expense (or deferred tax benefit)		$ 115
Provisional Transition Tax obligation		62
Gain on remeasurement of Tax Receivable Agreement liability		93
Undistributed accumulated earnings of foreign subsidiaries		1,100	$ 1,000
Accumulated earnings of foreign pass through subsidiaries		300	300
Accumulated earnings subject to additional foreign tax		$ 200	$ 200
Scenario, Plan [Member]
U.S. Statutory Tax Rate	21.00%

X

- Definition

Accumulated earnings attributable to our foreign subsidiaries that are considered pass-through entities for U.S. income tax purposes.

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Accumulated earnings of certain pass through subsidiaries where repatriation would result in additional foreign taxes in the form of dividend withholding tax imposed on the recipient of the distribution or dividend distribution tax imposed on the payor of the distribution.

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Gain on Remeasurement of Tax Receivable Agreement liability as result of the reduction in the U.S. corporate tax rate to 21%

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to repatriation of foreign earnings.

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