Shareholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions	1 Months Ended		3 Months Ended		12 Months Ended		15 Months Ended
	Jan. 31, 2016	Jan. 31, 2015	Apr. 03, 2016	Apr. 05, 2015	Dec. 31, 2016	Dec. 31, 2015	Apr. 03, 2016
Stockholders Equity Note Disclosure [Line Items]
Repurchase of stock, value			$ 28,000,000			$ 300,000,000
Repurchase of stock, shares			1.5
Cumulative repurchases, shares			17.1				17.1
Cumulative repurchases, value			$ 328,000,000				$ 328,000,000
Common stock average price			$ 18.81				$ 19.17
Dividends payable, amount per share	$ 0.06	$ 0.06
Dividends payable, date to be paid	Mar. 21, 2016	Mar. 24, 2015
Dividends payable, record date	Feb. 26, 2016	Feb. 27, 2015
Dividend payment			$ 12,253,000	$ 13,049,000
Maximum
Stockholders Equity Note Disclosure [Line Items]
Stock repurchase program, authorized amount		$ 500,000,000
Maximum | Scenario, Forecast
Stockholders Equity Note Disclosure [Line Items]
Repurchase of stock, value					$ 200,000,000
Minimum | Scenario, Forecast
Stockholders Equity Note Disclosure [Line Items]
Repurchase of stock, value					$ 100,000,000