Segmented information (Schedule of Revenue and Net income by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Segment Reporting [Line Items]
Revenue	$ 411,479	$ 329,682	$ 1,289,946	$ 1,057,598
Selling, general and administrative expenses ("SG&A")	133,193	106,508	404,077	330,307
Acquisition-related costs	2,031	10,255	15,067	16,226
Depreciation and amortization expenses ("D&A")	24,290	21,907	72,813	64,912
Foreign exchange loss (gain)	(430)	360	(752)	788
Total operating expenses	347,858	277,131	1,071,786	871,271
Gain on disposition of property, plant and equipment ("PPE")	(333)	(1,068)	(170,499)	(1,311)
Operating income	63,954	53,619	388,659	187,638
Interest expense	(9,199)	(8,807)	(48,348)	(26,620)
Change in fair value of derivatives, net			1,263
Debt extinguishment costs			(4,792)
Other income, net	2,866	602	5,426	2,800
Income tax expense	(14,697)	(13,057)	(72,564)	(42,541)
Net income	42,924	32,357	274,436	121,277
Operating Segments [Member]
Segment Reporting [Line Items]
Revenue	411,479	329,682	1,289,946	1,057,598
Selling, general and administrative expenses ("SG&A")	133,193	106,508	404,077	330,307
Segment profit	89,512	85,073	305,288	268,253
Acquisition-related costs	2,031	10,255	15,067	16,226
Depreciation and amortization expenses ("D&A")	24,290	21,907	72,813	64,912
Foreign exchange loss (gain)	(430)	360	(752)	788
Total operating expenses	347,858	277,131	1,071,786	871,271
Gain on disposition of property, plant and equipment ("PPE")	333	1,068	170,499	1,311
Operating income	63,954	53,619	388,659	187,638
Interest expense	(9,199)	(8,807)	(48,348)	(26,620)
Change in fair value of derivatives, net			1,263
Other income, net	2,866	602	5,426	2,800
Income tax expense	(14,697)	(13,057)	(72,564)	(42,541)
Net income	42,924	32,357	274,436	121,277
Auctions and Marketplaces [Member] | Operating Segments [Member]
Segment Reporting [Line Items]
Revenue	358,710	294,371	1,141,809	948,248
Selling, general and administrative expenses ("SG&A")	116,337	94,203	350,684	296,199
Segment profit	70,519	74,447	256,959	235,078
Other Reporting Unit [Member] | Operating Segments [Member]
Segment Reporting [Line Items]
Revenue	52,769	35,311	148,137	109,350
Selling, general and administrative expenses ("SG&A")	16,856	12,305	53,393	34,108
Segment profit	18,993	10,626	48,329	33,175
Service Revenues [Member]
Segment Reporting [Line Items]
Revenue	246,696	214,193	778,059	672,971
Direct expenses	41,521	35,108	125,575	114,275
Service Revenues [Member] | Operating Segments [Member]
Segment Reporting [Line Items]
Revenue	246,696	214,193	778,059	672,971
Direct expenses	41,521	35,108	125,575	114,275
Service Revenues [Member] | Auctions and Marketplaces [Member] | Operating Segments [Member]
Segment Reporting [Line Items]
Revenue	193,927	178,882	629,922	563,621
Direct expenses	24,601	22,728	79,160	72,208
Service Revenues [Member] | Other Reporting Unit [Member] | Operating Segments [Member]
Segment Reporting [Line Items]
Revenue	52,769	35,311	148,137	109,350
Direct expenses	16,920	12,380	46,415	42,067
Commissions
Segment Reporting [Line Items]
Revenue	108,238	110,275	361,016	343,584
Commissions | Operating Segments [Member]
Segment Reporting [Line Items]
Revenue	108,238	110,275	361,016	343,584
Commissions | Auctions and Marketplaces [Member] | Operating Segments [Member]
Segment Reporting [Line Items]
Revenue	108,238	110,275	361,016	343,584
Fees
Segment Reporting [Line Items]
Revenue	138,458	103,918	417,043	329,387
Fees | Operating Segments [Member]
Segment Reporting [Line Items]
Revenue	138,458	103,918	417,043	329,387
Fees | Auctions and Marketplaces [Member] | Operating Segments [Member]
Segment Reporting [Line Items]
Revenue	85,689	68,607	268,906	220,037
Fees | Other Reporting Unit [Member] | Operating Segments [Member]
Segment Reporting [Line Items]
Revenue	52,769	35,311	148,137	109,350
Inventory Sales Revenue [Member]
Segment Reporting [Line Items]
Revenue	164,783	115,489	511,887	384,627
Direct expenses	147,253	102,993	455,006	344,763
Inventory Sales Revenue [Member] | Operating Segments [Member]
Segment Reporting [Line Items]
Revenue	164,783	115,489	511,887	384,627
Direct expenses	147,253	102,993	455,006	344,763
Inventory Sales Revenue [Member] | Auctions and Marketplaces [Member] | Operating Segments [Member]
Segment Reporting [Line Items]
Revenue	164,783	115,489	511,887	384,627
Direct expenses	$ 147,253	$ 102,993	$ 455,006	$ 344,763