Fair value measurements (Details 4) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2021
Fair value, balance sheet grouping [Line Items]
Long-term debt	$ 2,927,967	$ 2,741,900	$ 2,337,049
Carrying amount
Fair value, balance sheet grouping [Line Items]
Long-term debt	2,927,967	2,741,900	2,337,049
Fair value
Fair value, balance sheet grouping [Line Items]
Long-term debt, fair value	$ 2,753,684	$ 2,984,866	$ 2,616,232

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant