Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended		86 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Feb. 20, 2020
Common Stock
Net of forfeitures for tax withholdings	13,516	122,319	13,516	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	57,731		519,562
Amount paid for shares purchased under share repurchase program	$ 0.9		$ 8.3
Amount paid for shares purchased and cancelled under share repurchase program (per share)	$ 16.46		$ 16.06
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			27,195	13,278
Granted, Units					597,008
Accrued dividend equivalent units	2,596		2,596		2,596