Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Earnings Per Share Reconciliation [Abstract]
Earnings from continuing operations	$ 22,634	$ 15,682
fair value adjustment to warrants, net of tax	(7,653)	0
Undistributed Earnings (Loss) from Continuing Operations Available to Common Shareholders, Diluted	$ 14,981	$ 15,682
Weighted-average shares outstanding for basic earnings per share (in shares)	58,838	58,840
Common equivalent shares:
Effect of stock-based compensation awards (in shares)	1,599	718
Weighted-average shares outstanding assuming dilution (in shares)	60,437	59,558
Basic earnings per share from continuing operations (in dollars per share)	$ 0.38	$ 0.27
Diluted earnings per share from continuing operations (in dollars per share)	$ 0.25	$ 0.26
Equivalent shares not included in weighted average shares outstanding because they would be anti-dilutive	9,200	9,700
Amazon Warrant AB [Member]
Earnings Per Share Reconciliation [Abstract]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	39,530		14,830