Real Estate Activities - Components of Total Investment in Financing Leases (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Direct Financing Lease Net Investment In Leases [Abstract]
Minimum lease payments receivable	$ 1,228,966	$ 1,884,921
Estimated residual values	203,818	394,195
Less: Unearned income and allowance for credit loss	(969,061)	(1,618,252)
Net investment in direct financing leases	463,723	660,864
Other financing leases (net of allowance for credit loss)	1,547,199	1,399,438
Total investment in financing leases	$ 2,010,922	$ 2,060,302