Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Mar. 31, 2018
Income per share
Strike price of the warrant transactions (in dollars per share)	$ 80.91				$ 80.91		$ 80.91
Numerator:
Net earnings	$ 7,865	$ 25,616	$ 23,726	$ 5,694	$ 33,481	$ 29,420
After-tax interest expense for 2023 Notes	888		0		1,775	0
Numerator for dilutive earnings per share	$ 8,753		$ 23,726		$ 35,256	$ 29,420
Denominator:
Weighted average shares outstanding, basic (in shares)	53,426,163		53,005,344		53,378,319	52,985,472
Effect of dilutive securities:
Stock options, RSU and SAR (in shares)	1,187,060		1,718,802		1,239,439	1,616,061
Convertible notes (in shares)			0		6,783,936	0
Weighted average shares outstanding, diluted (in shares)	61,397,159		54,724,146		61,401,694	54,601,533
Earnings per share, basic (in dollars per share)	$ 0.15		$ 0.45		$ 0.63	$ 0.56
Earnings per share, diluted (in dollars per share)	$ 0.14		$ 0.43		$ 0.57	$ 0.54
Stock options, RSUs, PSUs
Income per share
Common stock equivalents excluded in the calculation of diluted income per share (in shares)	283,299		1,157,397		556,565	1,313,316