Loans Receivable - Summary of Real Estate Loans Receivable (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019		Jun. 30, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan Carrying Value	$ 680,691
Allowance for credit losses on real estate loans receivable	(81,985)	$ (68,372)		$ (68,372)	$ (68,372)
Real estate loans receivable, net of credit allowance	224,871	270,382	[1]
Non-real estate loans	451,968	362,850
Allowance for credit losses on non-real estate loans receivable	(78,133)	(25,996)
Non real estate loans receivable, net of allowance	373,835	336,854
Total loans receivable, net of credit allowance	598,706	607,236
Mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan Carrying Value	102,275	188,062
Other real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan Carrying Value	126,448	124,696
Allowance for credit losses on real estate loans receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses on real estate loans receivable	$ (3,852)	$ (42,376)

[1] The consolidated balance sheet at December 31, 2019 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by U.S. generally accepted accounting principles for complete financial statements.