Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011
Cash flows from operating activities
Net income	$ 3,413	$ 3,060
Adjustments to reconcile net income including non-controlling interests to net cash provided by operating activities:
Depreciation and amortization of property and equipment	7,873	5,339
Amortization of intangible assets	482	1,069
Stock-based compensation	1,945	930
Forgiveness of note receivable from stockholder		103
Excess tax benefits from stock-based compensation	(588)
Change in fair value of preferred stock warrants		140
Change in deferred income taxes		234
Changes in operating assets and liabilities:
Accounts receivable	(505)	461
Unbilled receivables		(266)
Prepaid expenses and other assets	1,616	470
Accounts payable	214	(2,273)
Accrued expenses and other liabilities	(3,006)	(1,790)
Deferred revenue	1,876	2,423
Net cash provided by operating activities	13,320	9,900
Cash flows from investing activities
Increase in restricted cash		(52)
Purchases of marketable securities available-for-sale	(42,195)
Purchases of property and equipment	(10,675)	(9,793)
Contractual payments related to business acquisition	(14)	(81)
Net cash used in investing activities	(52,884)	(9,926)
Cash flows from financing activities
Excess tax benefits from stock-based compensation	588
Proceeds from exercise of stock options	1,885	558
Payments of capital leases	(174)	(237)
Payments to non-controlling interests	(642)	(547)
Proceeds from issuance of common stock upon initial public offering		48,297
Offering costs		(2,073)
Net cash provided by financing activities	1,657	45,998
Net decrease in cash and cash equivalents	(37,907)	45,972
Cash and cash equivalents at beginning of year	93,933	25,721
Cash and cash equivalents at end of year	56,026	71,693
Supplemental disclosure of cash flow information
Cash paid for taxes	279	1,173
Supplemental disclosure of non-cash investing and financing activities
Property and equipment and software maintenance costs in accounts payable, accrued expenses and other liabilities	3,363	2,093
Offering costs in accounts payable, accrued expenses and other liabilities		456
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.