The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Amount of gain (loss) on termination of lease before expiration of lease term.

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Amount of lease income from operating, direct financing, and sales-type leases. Includes, but is not limited to, variable lease payments, interest income, profit (loss) recognized at commencement, and lease payments paid and payable to lessor.

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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Summary of Significant Accounting Policies - Summary of Impact of Simultaneous Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 3,757	$ 2,459	$ 3,757	$ 14,517
Total Lease revenues, net	122,777	80,744	290,234	239,346
Loss on sale of properties	1,220	1,060	9,791	9,725
Lease Termination Impact
Finite-Lived Intangible Assets [Line Items]
Lease termination fee	35,000		35,000
Write-off of accrued rental income			1,496
Total Lease revenues, net			33,793
Loss on sale of properties	25,746		(25,746)
Increase to net income			4,001
Above and Below Market Leases \| Lease Revenues, Net
Finite-Lived Intangible Assets [Line Items]
Amortization expense	944	(149)	2,362	25
Above and Below Market Leases \| Lease Termination Impact \| Lease Revenues, Net
Finite-Lived Intangible Assets [Line Items]
Amortization expense			289
Acquired In-Place Leases \| Depreciation and Amortization
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 11,424	$ 8,026	25,429	$ 32,060
Acquired In-Place Leases \| Lease Termination Impact \| Depreciation and Amortization
Finite-Lived Intangible Assets [Line Items]
Amortization expense			$ (4,046)