Condensed Statements Of Cash Flows (USD $) In Thousands	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Cash flows from operating activities:
Net income	$ 18,858	$ 17,844
Adjustments to reconcile net income to net cash provided by operations:
Depreciation and amortization	7,778	8,077
Share-based compensation expense	4,585	4,617
Excess tax benefit from exercises of share-based arrangements	(1,721)	(1,209)
Changes in operating assets and liabilities, exclusive of effects of acquired companies:
Accounts receivable	6,423	3,837
Income tax payable	3,225	(78)
Prepaid expenses and other current assets	(655)	425
Accounts payable	1,110	(1,939)
Accrued liabilities	(22)	(3,551)
Deferred revenue	5,524	(759)
Net cash provided by operating activities	45,105	27,264
Cash flows from investing activities:
Proceeds from sale of investments	50	75
Cost of acquisitions, net of cash acquired		(9,661)
Additions to property and equipment	(9,926)	(4,197)
Decrease in restricted investments		6,000
Decrease (Increase) in other	199	(3)
Net cash used by investing activities	(9,677)	(7,786)
Cash flows from financing activities:
Purchase of treasury shares	(68,525)	(41,674)
Increase in net borrowings on revolving line of credit	31,500	16,500
Contributions from employee stock purchase plan	1,472	1,404
Proceeds from exercise of stock options	1,570	1,863
Debt issuance costs		(2,027)
Excess tax benefit from exercises of share-based arrangements	1,721	1,209
Net cash used by financing activities	(32,262)	(22,725)
Net increase (decrease) in cash and cash equivalents	3,166	(3,247)
Cash and cash equivalents at beginning of period	2,114	9,696
Cash and cash equivalents at end of period	$ 5,280	$ 6,449

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).