Loans Receivable and Other Lending Investments, net - Other Lending Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Available-for-Sale Securities
Amortized Cost Basis	$ 20,680
Estimated Fair Value	24,611
Held-to-Maturity Securities
Total	87,755
Estimated Fair Value	87,755
Total Other Lending Investments
Face Value	120,680	$ 121,140
Amortized Cost Basis	108,435	106,121
Net Unrealized Gain	3,931	2,756
Estimated Fair Value	112,366	108,877
Net Carrying Value	112,366	108,877
Municipal debt securities
Available-for-Sale Securities
Face Value	20,680	21,140
Amortized Cost Basis	20,680	21,140
Net Unrealized Gain	3,931	2,756
Estimated Fair Value	24,611	23,896
Net Carrying Value	24,611	23,896
Debt securities
Held-to-Maturity Securities
Face Value	100,000	100,000
Total	87,755	84,981
Net Unrealized Gain	0	0
Estimated Fair Value	87,755	84,981
Net Carrying Value	$ 87,755	$ 84,981