Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income per share
Strike price of the warrant transactions (in dollars per share)	$ 80.9063		$ 80.9063
Numerator:
Net earnings	$ 23,726	$ 34,667	$ 29,420	$ 56,185
Denominator:
Weighted average shares outstanding, basic (in shares)	53,005,344	52,557,035	52,985,472	52,545,910
Effect of dilutive securities:
Stock options, RSU and SAR (in shares)	1,718,802	1,088,793	1,616,061	1,065,508
Weighted average shares outstanding, diluted (in shares)	54,724,146	53,645,828	54,601,533	53,611,418
Earnings per share, basic (in dollars per share)	$ 0.45	$ 0.66	$ 0.56	$ 1.07
Earnings per share, diluted (in dollars per share)	$ 0.43	$ 0.65	$ 0.54	$ 1.05
Stock options, RSUs, PSUs
Income per share
Common stock equivalents excluded in the calculation of diluted income per share (in shares)	1,157,397	2,999,885	1,313,316	3,022,165
Convertible Debt
Income per share
Conversion price, per share of common stock (in dollars per share)	$ 59.33		$ 59.33