Notes Payable to Trusts (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2019 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2005 subsidiary
Variable Interest Entity [Line Items]
Variable interest entity interest in trust number | subsidiary					3
Principal payments on notes payable to trusts		$ 0	$ 30,928	$ 88,662
Notes payable to Trusts | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Principal payments on notes payable to trusts	$ 30,928			88,662
Notes payable to Trusts				$ 30,928