FAIR VALUE MEASUREMENTS - Summary of changes in Level 3 financial asset - Asset retirement obligation (Details 1) (Asset retirement obligations, USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2014
Asset retirement obligations
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, January 1, 2014	$ 2,357
Accrued estimated obligation, less fair value adjustment (note 5)	1,338
Accretion	165
Payments	(90)
Balance, September 30, 2014	$ 3,770

Represents the information about accrued estimated obligation, less fair value adjustment.

No definition available.

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Namespace Prefix:	inap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the information about asset retirement obligation payments.

+ References

No definition available.

+ Details

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Namespace Prefix:	inap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant