Summary of significant accounting policies.

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 55
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Present value of lessee's discounted obligation for lease payments from operating lease.

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-Publisher FASB
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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
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The amount of a reclassification adjustment made to prior period financial statement amounts.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Summary of Significant Accounting Policies (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jan. 01, 2019
Summary Of Significant Accounting Policies [Line Items]
Operating lease, right-of-use asset					$ 14,600,000
Operating lease, right-of-use liability	$ 13,992,000		$ 13,992,000
Operating lease cost	700,000		2,100,000
Total revenues	$ 35,912,000	$ 36,170,000	108,455,000	$ 115,088,000
Adjustment to opening equity prior period			$ 500,000
Rents [Member] \| Accounting Standards Update 2016-02 [Member]
Summary Of Significant Accounting Policies [Line Items]
Total revenues		28,100,000		85,700,000
Expense Recoveries [Member] \| Accounting Standards Update 2016-02 [Member]
Summary Of Significant Accounting Policies [Line Items]
Total revenues		$ 7,700,000		$ 24,800,000
Accounts Payable and Accrued Liabilities [Member]
Summary Of Significant Accounting Policies [Line Items]
Operating lease, right-of-use liability					$ 14,600,000