Notes Receivable - General Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Aggregate carrying values	$ 70,381	$ 70,381		$ 110,135
Transition adjustment	(831,265)	(831,265)		(495,514)
Credit loss		$ 32,784
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	7,811	$ 32,784
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	70,400	70,400		110,100
Credit loss reserve	$ 38,000	$ 38,000		$ 0