Stockholders' Equity - Additional Information (Detail) - USD ($)			12 Months Ended
	Feb. 04, 2016	Nov. 14, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class of Stock [Line Items]
Payment to acquire business				$ 46,300,000	$ 3,670,000,000
Repurchase of common stock	$ 500,000,000		$ 187,979,000	$ 8,119,000	$ 1,125,964,000
Stock repurchase program, period in force	18 months
Treasury stock retired (in shares)			1,259,145
Comdata Inc.
Class of Stock [Line Items]
Payment to acquire business		$ 3,400,000,000
Cash consideration		$ 2,400,000,000
Common shares issued to finance acquisition (in shares)		7,625,380
Repurchase Agreements
Class of Stock [Line Items]
Repurchase of common stock			$ 187,677,389