Consolidated 50% Owned Subsidiaries Consolidated 50% Owned Subsidiaries - Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Variable Interest Entity [Line Items]
Operating income	$ 12,103	$ 4,720
Net income	3,115	1,815
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Revenues	44,362	42,414
Operating income	155	277
Net income	$ 158	$ 282

Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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