Income taxes (Summary of valuation allowance) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Valuation allowance at beginning of period	$ 79,393	$ 74,361
GECAS Transaction	61,263	0
(Decrease) Increase of allowance included in income tax expense	11,421	5,032
Valuation allowance at end of period	$ 152,077	$ 79,393

Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Business Combination, Amount

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	duration