CAPITAL LEASES - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Schedule of Capital Lease Obligations [Line Items]
Increase in capital lease obligations	$ 19,565,000	$ 16,783,000
Voxel Holdings Incorporated
Schedule of Capital Lease Obligations [Line Items]
Increase in capital lease obligations	1,288,000
Assets Held under Capital Leases
Schedule of Capital Lease Obligations [Line Items]
Increase in leased property and equipment	19,600,000
Increase in capital lease obligations	19,600,000
Assets Held under Capital Leases | Network equipment under capital lease
Schedule of Capital Lease Obligations [Line Items]
Increase in leased property and equipment	2,400,000
Assets Held under Capital Leases | Data center space
Schedule of Capital Lease Obligations [Line Items]
Increase in leased property and equipment	$ 17,200,000
Capital Lease Obligations
Schedule of Capital Lease Obligations [Line Items]
Capital leases expiration dates	2013 to 2023