Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net loss	$ (224)us-gaap_NetIncomeLoss	$ (66)us-gaap_NetIncomeLoss
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation	2,107us-gaap_Depreciation	2,773us-gaap_Depreciation
Amortization of intangible assets	221us-gaap_AmortizationOfIntangibleAssets	539us-gaap_AmortizationOfIntangibleAssets
Net (gains) losses from investments	19us-gaap_GainLossOnInvestments	(37)us-gaap_GainLossOnInvestments
Deferred income taxes	109us-gaap_DeferredIncomeTaxExpenseBenefit	(132)us-gaap_DeferredIncomeTaxExpenseBenefit
Stock-based compensation	2,186us-gaap_ShareBasedCompensation	1,947us-gaap_ShareBasedCompensation
Amortization of premium on investments	187	391
Foreign currency (gains) losses	(166)	245
Changes in assets and liabilities
Accounts receivable	16,802	28,310
Deferred commissions	785	(72)
Prepaid expenses and other current assets	(5,449)	(2,934)
Accounts payable	(13)	137
Accrued expenses and other liabilities	(7,984)	(4,871)
Deferred revenue	7,702	6,774
Net cash provided by operating activities	16,282	33,004
Cash flows from investing activities:
Purchases of property and equipment	(948)	(680)
Purchases of marketable investments	(14,552)	(20,046)
Proceeds from sales and maturities of marketable investments	8,578	23,934
Other investing activity	204	1,391
Net cash provided by (used in) investing activities	(6,718)	4,599
Cash flows from financing activities:
Dividends paid on common stock	(3,069)us-gaap_PaymentsOfDividendsCommonStock	(3,135)us-gaap_PaymentsOfDividendsCommonStock
Repurchases of common stock	(5,723)	(29,712)
Proceeds from issuance of common stock under employee equity incentive plans	1,349	1,556
Excess tax benefits from stock-based compensation	20	22
Net cash used in financing activities	(7,423)	(31,269)
Effect of exchange rate changes on cash and cash equivalents	(1,623)	35
Net increase in cash and cash equivalents	518	6,369
Cash and cash equivalents, beginning of period	49,650	74,132
Cash and cash equivalents, end of period	$ 50,168	$ 80,501

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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.