CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash Flows from Operating Activities:
Net loss	$ (4,318)	$ (1,702)	$ (3,622)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	40,865	40,426	33,969
(Gain) loss on disposal of property and equipment, net	(55)	37	116
Impairment of capitalized software	438	526
Stock-based compensation expense, net of capitalized amount	5,858	3,983	4,631
Equity in (earnings) of equity-method investment	(220)	(475)	(396)
Provision for doubtful accounts	932	1,082	1,253
Non-cash change in capital lease obligations	705	1,044	630
Non-cash change in accrued contingent consideration	124
Non-cash change in deferred rent	(1,073)	(555)	237
Deferred income taxes	204	(5,734)	471
Other, net	521	263
Changes in operating assets and liabilities:
Accounts receivable	(1,428)	(1,186)	(156)
Prepaid expenses, deposits and other assets	(671)	(2,282)	(2,577)
Accounts payable	413	(5,209)	8,147
Accrued and other liabilities	2,304	(247)	(1,216)
Deferred revenues	862	(970)	(907)
Exit activities and restructuring liability	(1,719)	(371)	(978)
Net cash flows provided by operating activities	43,742	28,630	39,602
Cash Flows from Investing Activities:
Purchases of property and equipment	(74,947)	(68,542)	(62,184)
Payment of accrued contingent consideration	(4,750)
Voxel acquisition, net of cash received		(27,723)
Maturities of investments in marketable securities			7,000
Net cash flows used in investing activities	(79,697)	(96,265)	(55,184)
Cash Flows from Financing Activities:
Proceeds from credit agreement	40,401	39,853	78,036
Principal payments on credit agreement	(3,250)	(1,000)	(78,750)
Payment of debt issuance costs	(543)	(253)	(518)
Payments on capital lease obligations	(3,303)	(1,190)	(446)
Proceeds from exercise of stock options	2,469	1,372	3,420
Tax withholdings related to net share settlements of restricted stock awards	(1,085)	(746)	(393)
Other, net	(118)	(135)	(125)
Net cash flows provided by financing activities	34,571	37,901	1,224
Effect of exchange rates on cash and cash equivalents	165	(76)	14
Net decrease in cash and cash equivalents	(1,219)	(29,810)	(14,344)
Cash and cash equivalents at beginning of period	29,772	59,582	73,926
Cash and cash equivalents at end of period	28,553	29,772	59,582
Supplemental disclosure of cash flow information:
Cash paid for interest	7,646	3,293	2,058
Cash paid for income taxes	189	267	395
Non-cash acquisition of property and equipment under capital leases	10,079	19,565	16,783
Capitalized stock-based compensation	$ 427	$ 516	$ 178