Notes Receivable - General Information (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Aggregate carrying values	$ 82,542	$ 82,542		$ 110,135
Transition adjustment	(711,798)	(711,798)		(495,514)
Credit loss		24,973
Credit loss		$ 24,973
Cumulative Effect, Period of Adoption, Adjustment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transition adjustment			$ (5,300)
Bonds A Series [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maturity date of notes receivable		Jul. 01, 2034
Bonds B Series [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maturity date of notes receivable		Sep. 01, 2037
Credit loss	19,145	$ 24,973
Bonds B Series [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transition adjustment			$ (5,200)
Bonds A and B Series [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Aggregate carrying values	82,500	82,500		110,100
Credit loss reserve	$ 30,200	$ 30,200		$ 0