Real Estate and Other Activities - Components of Total Investment in Financing Leases (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Direct Financing Lease Net Investment In Leases [Abstract]
Minimum lease payments receivable	$ 1,206,411	$ 1,228,966
Estimated residual values	203,818	203,818
Less: Unearned income and allowance for credit loss	(943,865)	(969,061)
Net investment in direct financing leases	466,364	463,723
Other financing leases (net of allowance for credit loss)	1,565,817	1,547,199
Total investment in financing leases	$ 2,032,181	$ 2,010,922