Accounting policies and related matters.

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- Definition

Number of leases.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; excluding effect from exchange rate change. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 230
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=98513438&loc=d3e33268-110906

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3521-108585

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- Definition

Amount of increase (decrease) in operating assets classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717

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Accounting Policies and Related Matters - Additional Information (Details) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2018 USD ($) Lease	Jun. 30, 2017 USD ($)	Dec. 31, 2018 USD ($)
Accounting Policies And Related Matters [Line Items]
Decrease in the change in other assets	$ (5,493)	$ 1,446
Number of leases \| Lease	2
Ground Lease
Accounting Policies And Related Matters [Line Items]
Number of leases \| Lease	1
Corporate Office Lease
Accounting Policies And Related Matters [Line Items]
Number of leases \| Lease	1
Ground Lease and Corporate Office Lease \| Scenario, Forecast
Accounting Policies And Related Matters [Line Items]
Operating leases, expected rent expense			$ 500
Accounting Standards Update 2016-18
Accounting Policies And Related Matters [Line Items]
Increase in the beginning of period cash, cash equivalents and restricted cash		300
Decrease in the change in other assets		$ 300