Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended		89 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Feb. 20, 2020
Common Stock
Net of forfeitures for tax withholdings	54,635		122,319
Share repurchase plan
Aggregate purchase price up to which shares can be acquired under share repurchase program					$ 25.0
Number of shares purchased under share repurchase program	174,698	694,260
Amount paid for shares purchased under share repurchase program	$ 3.1	$ 11.5
Amount paid for shares purchased and cancelled under share repurchase program (per share)	$ 17.80	$ 16.50
LTR Plan
Common Stock
Shares of common stock issued under the long-term incentive plan		34,524	114,106
Amount received in exchange for shares of common stock under a long term incentive plan		$ 0.6	$ 1.8
Percentage of average market closing prices used in determining number of common stock that could be purchased by participants		75.00%	75.00%
Equity Plan
Common Stock
Shares of common stock issued as a part of quarterly compensation of non-employee members of the Board of Directors		36,281	30,155
Granted, Units				583,484
Accrued dividend equivalent units	2,652	2,652		2,652