Stockholders' Equity - Additional Information (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Aug. 09, 2013
Class Of Stock [Line Items]
Preferred stock redemption date	Aug. 09, 2013
Preferred stock dividend rate			5.50%
Preferred stock outstanding			0	61,735
Number of Preferred shares converted			60,900
Number of common shares issued upon conversion of preferred stock			139,029
Preferred shares redeemed			835
Aggregate redemption price			$ 25.26354
Treasury stock, shares	3,428,541	3,384,443
Shares purchased during period	41,915	154,633	60,595
Treasury stock distributed under deferred compensation plan	4,563
Stock purchased to settle employees statutory withholding taxes relates to performance stock awards and deferred compensation distribution	6,746
Open Market Repurchases [Member]
Class Of Stock [Line Items]
Shares purchased during period	41,915
Price per share [Member]
Class Of Stock [Line Items]
Aggregate redemption price			$ 25.00
Accrued and Unpaid Dividends [Member]
Class Of Stock [Line Items]
Aggregate redemption price			$ 0.26354