Basis of presentation.

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- Definition

Payments on account of employee tax withholdings on share based awards.

+ References

No definition available.

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- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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- Definition

Amount of each individual error being corrected in the correcting adjustment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 1.N)
-URI http://asc.fasb.org/extlink&oid=26874127&loc=d3e30840-122693

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Basis of Presentation (Textual) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2017	Jun. 30, 2016
Basis Of Presentation [Line Items]
Shares used for employee taxes upon vesting of share awards			$ 674	$ 879
ASU 2016-09 [Member] \| Reclassified from Operating Activities to Financing Activities [Member]
Basis Of Presentation [Line Items]
Shares used for employee taxes upon vesting of share awards				879
ASU 2016-15 [Member] \| Reclassified from Operating Activities to Financing Activities [Member]
Basis Of Presentation [Line Items]
Debt prepayment costs				$ 53,400
Impairment Charges [Member]
Basis Of Presentation [Line Items]
Out-of-period adjustment		$ 1,200	1,200
Depreciation Expense Relating To Write Off [Member] \| Tenant Improvement Assets [Member]
Basis Of Presentation [Line Items]
Out-of-period adjustment	$ 1,900		$ 1,900