Consolidated income tax provision (benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Summary of consolidated income tax provision (benefit)
Current income taxes	$ 519	$ (86)
Deferred income taxes	(22,101)	1,014
Income tax provision (benefit)	$ (21,582)	$ 928

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Name:	us-gaap_DeferredIncomeTaxExpenseBenefit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration