Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income from continuing operations	$ 13,657	$ 3,526
Adjustments to reconcile net income from continuing operations to net cash provided by continuing operations:
Depreciation and amortization	1,469	1,566
Deferred tax expense (benefit)	1,151	(869)
Stock-based compensation	795us-gaap_ShareBasedCompensation	598us-gaap_ShareBasedCompensation
Changes in assets and liabilities:
Accounts receivable, net	(3,968)	7,082
Inventories	1,178us-gaap_IncreaseDecreaseInInventories	(164)us-gaap_IncreaseDecreaseInInventories
Foreign sales tax receivable	366	(37)
Other current assets	(860)	(85)
Accounts payable	(547)	236
Income taxes payable	393	(263)
Accrued expenses	(1,208)	592
Deferred compensation	(721)	(109)
Deferred revenue	582	(746)
Net cash provided by operating activities of continuing operations	12,287	11,327
Cash flows from investing activities of continuing operations:
Purchase of short term investments	(39,871)	0
Maturities of short term investments	29,931	0
Additions to property and equipment	(320)	(352)
Additions to intangible assets	(11)	(51)
Other assets	(6)	(1)
Net cash used in investing activities of continuing operations	(10,277)	(404)
Cash flows from financing activities of continuing operations:
Proceeds from exercise of stock options, net	0	51
Tax payments for restricted stock issuances	(837)	(123)
Tax benefit of stock-based compensation	410	35
Net cash used in financing activities of continuing operations	(427)	(37)
Cash flows used in discontinued operations:
Net cash used in operating activities of discontinued operations	0	(38)
Net cash used in discontinued operations	0	(38)
Effect of exchange rate changes on cash	183	37
Net increase in cash	1,766	10,885
Cash and equivalents, beginning of year	72,441	98,607
Cash and equivalents, end of period	$ 74,207	$ 109,492

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.