CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Millions	Total	Class A Common Stock	Additional Paid-in Capital	Treasury Stock	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning Balance at Dec. 31, 2016	$ 792	$ 1	$ 210	$ (614)	$ 1,240	$ (45)
Beginning Balance, Shares at Dec. 31, 2016		52,884,588
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of treasury shares upon exercise of stock options, purchases under stock purchase plan and grants of restricted stock awards, net of cancellations (in shares)		410,239
Issuance of treasury shares upon exercise of stock options, purchases under stock purchase plan and grants of restricted stock awards, net of cancellations	12		12
Shares withheld related to net share settlement (in shares)		(58,732)
Shares withheld related to net share settlement	(6)			(6)
Share-based compensation	35		35
Net income	17				17
Changes in unrealized gains and losses on anticipated sales hedging transactions (net of income taxes)	(15)					(15)
Changes in unrealized gains and losses on forward interest rate swap hedging transactions (net of income taxes)	6					6
Foreign currency translation adjustment	2					2
Ending Balance at Dec. 31, 2017	834	$ 1	257	(620)	1,248	(52)
Ending Balance, Shares at Dec. 31, 2017		53,236,095
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of treasury shares upon exercise of stock options, purchases under stock purchase plan and grants of restricted stock awards, net of cancellations (in shares)		704,137
Issuance of treasury shares upon exercise of stock options, purchases under stock purchase plan and grants of restricted stock awards, net of cancellations	10		(8)	18
Shares withheld related to net share settlement (in shares)		(69,048)
Shares withheld related to net share settlement	(11)			(11)
Share-based compensation	45		45
Net income	421				421
Changes in unrealized gains and losses on anticipated sales hedging transactions (net of income taxes)	21					21
Changes in unrealized gains and losses on forward interest rate swap hedging transactions (net of income taxes)	9					9
Foreign currency translation adjustment	(13)					(13)
Ending Balance at Dec. 31, 2018	1,335	$ 1	294	(613)	1,688	(35)
Ending Balance, Shares at Dec. 31, 2018		53,871,184
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of treasury shares upon exercise of stock options, purchases under stock purchase plan and grants of restricted stock awards, net of cancellations (in shares)		594,399
Issuance of treasury shares upon exercise of stock options, purchases under stock purchase plan and grants of restricted stock awards, net of cancellations	11		(3)	14
Shares withheld related to net share settlement (in shares)		(224,765)
Shares withheld related to net share settlement	(43)			(43)
Share-based compensation	48		48
Repurchase of common stock (in shares)		(237,886)
Repurchase of common stock	(47)			(47)
Net income	544				544
Changes in unrealized gains and losses on anticipated sales hedging transactions (net of income taxes)	(10)					(10)
Foreign currency translation adjustment	1					1
Ending Balance at Dec. 31, 2019	$ 1,839	$ 1	$ 339	$ (689)	$ 2,232	$ (44)
Ending Balance, Shares at Dec. 31, 2019		54,002,932