Share Repurchase Program (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Nov. 01, 2016
Equity, Class of Treasury Stock [Line Items]
Amount available under the share repurchase program	$ 81,900,000
Purchase of treasury stock (in shares)	1,280,802	0	750,000
Treasury stock repurchased (in dollars per share)	$ 6.64		$ 12.83
Purchase of treasury stock	$ 8,500,000		$ 9,640,000
2016 Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Authorized share repurchased program amount				$ 100,000,000