Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Cash flows from operating activities
Net income	$ 2,056	$ 5,377
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization and depreciation	11,146	11,070
Provision for prompt payment discounts	2,781	2,909
Provision for inventory allowances	339	199
Loss on sale of property and equipment		25
Impairment of product rights	2,500
Stock-based compensation	1,586	970
Benefit from (provision for) deferred income taxes	1,223	(1,419)
Changes in operating assets and liabilities:
Accounts receivable	56,615	(2,206)
Inventories	2,540	(1,855)
Prepaid expenses, long-term accounts receivable and other assets	7,508	1,523
Accounts payable	2,003	2,172
Accrued expenses and license agreement liability	(3,083)	5,087
Income taxes receivable	(2,007)	(2,597)
Deferred revenue	(54,856)	9,195
Net cash provided by operating activities	30,351	30,450
Cash flows from investing activities
Proceeds from sale of property and equipment		2
Purchase of property and equipment	(574)	(361)
Purchase of product rights		(250)
Net cash used in investing activities	(574)	(609)
Cash flows from financing activities
Proceeds from exercise of common stock options	368	538
Excess tax benefit from stock-based compensation	513	467
Principal payments on capital lease obligation	(62)	(27)
Net cash provided by financing activities	819	978
Net increase in cash and cash equivalents	30,596	30,819
Cash and cash equivalents as of beginning of period	50,945	18,853
Cash and cash equivalents as of end of period	$ 81,541	$ 49,672

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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).