Property and Equipment, Net - Amounts under Capital Lease Obligations (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Various equipment under capital lease arrangements
Gross	$ 98,004	$ 57,114
Accumulated Amortization	(48,847)	(42,848)
Net	49,157	14,266
Computer and other equipment
Various equipment under capital lease arrangements
Gross	92,553	51,702
Accumulated Amortization	(44,327)	(39,060)
Furniture and other equipment
Various equipment under capital lease arrangements
Gross	5,451	5,412
Accumulated Amortization	$ (4,520)	$ (3,788)

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84164817&loc=d3e45280-112737

+ Details

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- Definition

The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=84164758&loc=d3e45014-112735

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 2)
-URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697

+ Details

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