Summary of Significant Accounting Policies - Deferred Costs & Impairment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Summary of Significant Accounting Policies
Impairment loss related to intangible assets	$ 0	$ 0	$ 0	$ 0
Goodwill	40,646		40,646		$ 40,646
Impairment loss related to goodwill	0	0	0	0
Deferred Costs
Amortization of initial direct costs	4,000	4,100	11,800	12,200
Internal sales commissions	15,037		15,037		17,402
Third party commissions	10,021		10,021		11,802
Other	640		640		775
Total	25,698		25,698		$ 29,979
Recoverability of Long-Lived Assets
Impairment of real estate	$ 0	$ 0	$ 0	$ 0

Represents the amount of internal sales commissions.

No definition available.

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Balance Type:	debit
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- Definition

Represents the amount of other initial direct costs.

+ References

No definition available.

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- Definition

Represents the amount of third party commissions.

+ References

No definition available.

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- References

No definition available.

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- Definition

This element represents costs incurred by the lessor that are (a) costs to originate a lease incurred in transactions with independent third parties that (i) result directly from and are essential to acquire that lease and (ii) would not have been incurred had that leasing transaction not occurred and (b) certain costs directly related to specified activities performed by the lessor for that lease. Those activities are: evaluating the prospective lessee's financial condition; evaluating and recording guarantees, collateral, and other security arrangements; negotiating lease terms; preparing and processing lease documents; and closing the transaction. This element is net of accumulated amortization.

+ References

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

+ References

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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- References

No definition available.

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- Definition

Amount of operating lease initial direct cost recognized as expense over lease term.

+ References

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-Publisher FASB
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-Topic 842
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