Stockholders' Equity - Cash Dividends Declared to Stockholders (Detail) - USD ($)			3 Months Ended								12 Months Ended			36 Months Ended	39 Months Ended
	Mar. 30, 2015	Apr. 26, 2013	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2015	Dec. 10, 2015	Sep. 10, 2015	Jun. 25, 2015	Mar. 04, 2015	Dec. 10, 2014	Sep. 10, 2014	Jun. 25, 2014	Mar. 28, 2014	Dec. 10, 2013	Sep. 10, 2013	Jun. 25, 2013	Mar. 29, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Per Share Amount																			$ 0.125
Total Payment			$ 3,555	$ 3,003	$ 2,547	$ 3,238	$ 3,133	$ 1,935	$ 1,979	$ 2,247					$ 21,637
Common Stockholders
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Per Share Amount											$ 0.01625			$ 0.01625	$ 0.01625
Total Payment														$ 37,114,000
Dividend Paid | Common Stockholders
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Per Share Amount	$ 0.00125					$ 0.00500					$ 0.00625	$ 0.00500	$ 0.00500	$ 0.00625	$ 0.00625	$ 0.00250	$ 0.00125	$ 0.00125		$ 0.00125	$ 0.00125	$ 0.00125	$ 0.00125	$ 0.00125	$ 0.00125	$ 0.00125	$ 0.00125
Total Payment	$ 643,000	$ 1,513,000									$ 13,976,000	$ 10,826,000	$ 12,312,000