Other current assets (Narrative) (Details)			3 Months Ended
	Mar. 17, 2022 USD ($)	Mar. 17, 2022 CAD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds on disposition of assets			$ 164,659,000	$ 66,000
Initial lease term	2 years	2 years
Recognized gain on disposition of property, plant and equipment	$ 169,092,000
Lease term	2 years
Renewal term	1 year
Assets held for sale			$ 10,830,000		$ 17,538,000
Bolton, Ontario [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Lease term	2 years
Sale consideration	$ 165,000,000	$ 208,195,000
Net book value of property plant and equipment	$ 7,067,000
Arizona, United States [Member] | Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets held for sale					$ 10,500,000