EMPLOYEE RETIREMENT PLAN - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Defined Benefit Plan Disclosure [Line Items]
Defined contribution retirement savings plan, employer contributions	$ 0.7	$ 0.8	$ 0.7

Defined Contribution Retirement Program Contributions

No definition available.

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