Earnings per share attributable to stockholders (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Net income (loss) attributable to:
Basic	$ 53,365	$ 60,749	$ 231,459	$ 88,937
Diluted	$ 53,365	$ 60,749	$ 231,459	$ 88,937
Weighted average number of shares outstanding:
Basic	110,760,339	110,311,615	110,705,182	110,144,229
Effect of dilutive securities:		111,334,184
Diluted	111,705,102	111,334,184	111,681,644	111,302,711
Per Share Amount
Basic	$ 0.48	$ 0.55	$ 2.09	$ 0.81
Diluted	$ 0.48	$ 0.55	$ 2.07	$ 0.80
Share Units [Member]
Weighted average number of shares outstanding:
Effect of dilutive securities:	397,274	322,371	423,767	450,752
Per Share Amount
Effect of dilutive securities:			(0.01)
Stock Options [Member]
Weighted average number of shares outstanding:
Effect of dilutive securities:	547,489		552,695	707,730
Diluted		700,198
Per Share Amount
Effect of dilutive securities:			(0.01)	(0.01)