Stockholders' Equity - Additional Information (Detail) - USD ($)		3 Months Ended		6 Months Ended
	Jul. 07, 2016	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015		Jul. 31, 2015	Aug. 31, 2007
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock repurchase program, number of shares authorized to be repurchased									20,000,000
Treasury stock value		$ 1,304,700,000		$ 1,304,700,000		$ 1,265,700,000	[1]
Common stock in treasury, shares		30,429,339		30,429,339		29,612,337
Subsequent Event [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Dividends declared date	Jul. 07, 2016
Dividends declared payable date	Sep. 16, 2016
Dividends declared date of record	Sep. 02, 2016
Dividends per share on common stock	$ 0.16
Common Stock Repurchase Set Two | Share Trading Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Treasury stock value			$ 80,000,000		$ 125,000,000
Number of common stock shares repurchased			1,610,287		2,624,434
Common Stock Repurchase Set One | Share Trading Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Treasury stock value		$ 20,000,000		$ 52,000,000
Number of common stock shares repurchased		435,140		1,134,485
Accelerated Shares Repurchase Agreement [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Treasury stock value			$ 25,000,000		$ 25,000,000
Common stock in treasury, shares			546,574		546,574
Common stock repurchase price per share					$ 45.74
Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock repurchase program, authorized amount								$ 1,500,000,000

[1] As of January 1, 2016, we have adopted ASU 2015-03 and ASU 2015-15 with retrospective application. This resulted in a reclassification from other non-current assets to long-term debt, less current portion for debt issuance costs. Refer to Note 2, “Recently Issued Accounting Standards” of the notes to the condensed consolidated financial statements for further details.