Stock Repurchase Program (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Nov. 30, 2012
Equity, Class of Treasury Stock [Line Items]
Repurchase of common stock			$ 609,000
Stock repurchase program, remaining amount	$ 54,900,000		$ 54,900,000
Share Repurchase Program, November 2012 [Member]
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount (up to)					$ 25,000,000
Repurchase of common stock during period (in shares)	0	367,129	0	547,319
Repurchase of common stock		$ 4,600,000		$ 7,300,000
Repurchase of common stock (in dollars per share)		$ 12.55		$ 13.26
Share Repurchase Program, June 2015 [Member]
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount (up to)		$ 50,000,000		$ 50,000,000
Repurchase of common stock (in shares)	0		0
Credit Facility
Equity, Class of Treasury Stock [Line Items]
Debt Instrument, Covenant, Share Repurchase, Maximum			$ 4,900,000