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Stockholders' Equity - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Feb. 28, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)	2,920,251		2,920,251
Authorized Amount					$ 300
Repurchase of common stock (in shares)	307,046	300,900	1,482,655	895,699
Repurchase of common stock			$ 84
Amount available for further repurchases under stock repurchase program	$ 292		$ 292
Time-Based Restricted Stock Units and Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			4 years
Performance-Based Restricted Stock Units and Restricted Stock Awards [Member] \| Tranche 1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			1 year
Vesting percentage			50.00%
Minimum \| Time-Based Restricted Stock Units and Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent of share value			0.00%
Maximum \| Time-Based Restricted Stock Units and Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent of share value			200.00%