Stock incentive plan - Non vested restricted stock award (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ending Balance	5,514	5,793
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance	23,734
Shares, Granted	3,341
Shares, Vested	(11,270)
Shares, Forfeited	(924)	0
Shares, Other	1,435
Ending Balance	16,316	17,077
Weighted-Average Grant-Date Fair-Value, Beginning Balance	$ 37.46
Weighted-Average Grant-Date Fair-Value, Granted	54.56
Weighted-Average Grant-Date Fair-Value, Vested	32.30
Weighted-Average Grant-Date Fair-Value, Forfeited	34.30
Weighted-Average Grant Date Fair Value, Other	32.32
Weighted-Average Grant-Date Fair-Value, Ending Balance	$ 44.25
Aggregate Intrinsic Value, Beginning Balance	$ 1,142,792
Aggregate Intrinsic Value, Granted	160,869
Aggregate Intrinsic Value, Vested	(542,651)
Aggregate Intrinsic Value, Forfeited	(44,491)
Aggregate Intrinsic Value, Other	69,095
Aggregate Intrinsic Value, Ending Balance	$ 785,615