Stockholders' Equity - Additional Information (Details) - USD ($)				3 Months Ended				9 Months Ended	12 Months Ended
	Sep. 30, 2014	Jul. 02, 2014	Jan. 31, 2008	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Sep. 29, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jan. 11, 2016	Jul. 30, 2014
Class of Stock [Line Items]
Preferred stock, shares authorized				50,000,000					50,000,000	50,000,000
Preferred stock, par value				$ 0.01					$ 0.01	$ 0.01
Preferred shares outstanding				0					0	0
Terms of conversion - closing price of common stock		$ 22.24
Terms of conversion - consecutive trading days		20 days
Common stock conversion price of preferred shares		$ 11.93
Conversion notice period		90 days
Common stock, shares authorized				450,000,000					450,000,000	450,000,000
Common stock, par value				$ 0.01					$ 0.01	$ 0.01
Common stock, shares issued				150,751,064					150,751,064
Common stock, shares outstanding				143,938,280					143,938,280	150,068,040
Treasury stock, shares				6,812,784					6,812,784	23,963
Quarterly dividend declared				$ 0.06	$ 0.06	$ 0.06	$ 0.06		$ 0.24	$ 0.23	$ 0.20
Aggregated dividends declared									$ 35,000,000	$ 37,000,000	$ 32,000,000
Aggregate dividends paid									35,000,000	$ 37,000,000	$ 32,000,000
Treasury stock reissued											14,879,935
Treasury stock reissued, charge to additional paid-in capital											$ 127,000,000
Treasury shares retired										18,100,000	14,600,000
Treasury stock retired, charge to additional paid-in capital										$ 0	$ 0
Share repurchase program amount												$ 1,700,000,000	$ 1,400,000,000
Cash spent to repurchase common stock									$ 81,000,000	311,000,000	$ 260,000,000
Shares repurchased									6,612,537
Stock Repurchase Program, Remaining Authorized Repurchase Amount				$ 219,000,000					$ 219,000,000
Series B Preferred Stock [Member]
Class of Stock [Line Items]
Preferred shares issued			5,400,000.0
Preferred stock dividend rate percentage			4.00%
Shares of preferred stock converted	1,506,972							2,296,802			1,772,693
Common shares issued upon conversion	12,631,780							19,517,593
Total fair value of the conversions	$ 250,000,000							$ 409,000,000
Additional Paid-in Capital [Member]
Class of Stock [Line Items]
Treasury stock retired, charge to additional paid-in capital										$ 346,000,000	$ 294,000,000