Subsequent Events - Additional Information (Detail) $ in Thousands	Feb. 11, 2016 shares	Jan. 01, 2016 USD ($) Employees	Mar. 09, 2016 USD ($) shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($) shares	Dec. 31, 2013 shares
Subsequent Event [Line Items]
Shares repurchased				73,228,000	69,333,000
Shares repurchased, value | $				$ 462,167	$ 425,685
Stock repurchase program authorized to be repurchased				3,800,000	3,200,000	0
Subsequent Event [Member]
Subsequent Event [Line Items]
Shares repurchased			600,000
Shares repurchased, value | $			$ 6,100
Renewal period of share repurchase	12 years
Stock repurchase program authorized to be repurchased	5,000,000
Expiration date of share authorization	Mar. 31, 2017
Subsequent Event [Member] | Millimaki Eggert, L.L.P [Member]
Subsequent Event [Line Items]
Number of employees | Employees		12
Annual revenue | $		$ 2,400
Subsequent Event [Member] | Maximum [Member]
Subsequent Event [Line Items]
Additional shares of outstanding common stock authorized	5,000,000