Recent Accounting Pronouncements Recent Accounting Pronouncements (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Cumulative Effect of New Accounting Principle in Period of Adoption	$ (4,225,000)
Operating Leases, Income Statement, Lease Revenue	76,527,000	$ 70,953,000
Financing Receivable, Allowance for Credit Loss	5,500,000
Off-Balance Sheet, Credit Loss, Liability	300,000
Escrow Funds Received From Tenants [Member]
Operating Leases, Income Statement, Lease Revenue	1,553,000	$ 1,090,000
Accounting Standards Update 2018-11 [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	0
Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss	3,900,000
Off-Balance Sheet, Credit Loss, Liability	$ 325,000

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

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