Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011
Cash flows from operating activities
Net income	$ 6,474	$ 4,860
Adjustments to reconcile net income including non-controlling interests to net cash provided by operating activities:
Depreciation and amortization of property and equipment	11,672	8,894
Amortization of intangible assets	778	1,392
Stock-based compensation	2,163	2,275
Forgiveness of note receivable from stockholder		103
Excess tax benefits from stock-based compensation	(1,041)
Change in fair value of preferred stock warrants		140
Change in deferred income taxes	(420)	(857)
Changes in operating assets and liabilities:
Accounts receivable	(4,053)	2,054
Unbilled receivables	671	(304)
Prepaid expenses and other assets	1,767	54
Accounts payable	(821)	55
Accrued expenses and other liabilities	(3,552)	419
Deferred revenue	3,596	901
Net cash provided by operating activities	17,234	19,986
Cash flows from investing activities
Increase in restricted cash		(65)
Purchases of marketable securities available-for-sale	(52,232)
Sales of marketable securities	15,013	1,000
Acquisition, net of cash acquired	(3,185)
Purchases of property and equipment	(15,755)	(13,154)
Contractual payments related to business acquisition	(14)	(127)
Net cash used in investing activities	(56,173)	(12,346)
Cash flows from financing activities
Excess tax benefits from stock-based compensation	1,041
Proceeds from exercise of stock options	2,125	602
Payments of capital leases	(190)	(330)
Payments to non-controlling interests	(620)	(547)
Proceeds from issuance of common stock upon initial public offering		48,297
Offering costs		(2,529)
Net cash provided by financing activities	2,356	45,493
Net decrease in cash and cash equivalents	(36,583)	53,133
Cash and cash equivalents at beginning of year	93,933	25,721
Cash and cash equivalents at end of year	57,350	78,854
Supplemental disclosure of cash flow information
Cash paid for taxes	650	1,194
Supplemental disclosure of non-cash investing and financing activities
Property and equipment and software maintenance costs in accounts payable, accrued expenses and other liabilities	4,129	2,247
Accretion of convertible preferred stock		1,633
Conversion of convertible preferred stock into common stock		124,602
Exercise and conversion of preferred stock warrants into common stock		$ 272

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.