Common Stock Repurchases - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Feb. 28, 2015
Common Stock Repurchases [Line Items]
Stock repurchase program expiration month and year			2016-02
Aggregate cost of shares repurchased	$ 7,200,000		$ 9,200,000
Number of shares repurchased	752,635	0	964,935	0
Maximum
Common Stock Repurchases [Line Items]
Repurchase of authorized common stock					$ 50,000,000