Real Estate Loans Receivable - Summary of Real Estate Loans Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019		Mar. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan Carrying Value	$ 674,978
Allowance for credit losses on real estate loans receivable	(80,571)	$ (68,372)		$ (87,062)	$ (68,372)
Real estate loans receivable, net of credit allowance	221,228	270,382	[1]
Real estate loans receivable, net of credit allowance	594,407
Non-real estate loans	451,271	362,850
Allowance for credit losses on non-real estate loans receivable	(78,092)	(25,996)
Non real estate loans receivable, net of allowance	373,179	336,854
Total loans receivable, net of credit allowance	594,407	607,236
Mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan Carrying Value	97,896	188,062
Other real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan Carrying Value	125,811	124,696
Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses on real estate loans receivable	$ (2,479)	$ (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.