Fair Value Measurements (Schedule Of Fair Values Of Financial Instruments Measured On Recurring Basis) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Available-for-sale Securities	$ 93,266	$ 158,158
Certificates of Deposit, at Carrying Value	63	60
Total assets	173,807	208,089
Business Combination, Contingent Consideration, Liability	13,661	30,600
Derivative Liability	1,450	1,450
Financial Liabilities Fair Value Disclosure	15,111	32,050
Debt Securities Issued By States Of The United States And Political Subdivisions Of The States [Member]
Investments	5,531	6,103
Money Market Funds [Member]
Cash	80,405	46,867
Bank Time Deposits [Member]
Cash	73	3,004
Certificates of Deposit [Member]
Investments	63	60
Equity Securities [Member]
Investments		22,654
Variable Rate Demand Obligation [Member]
Investments	2,400
Debt Securities Issued By The U.S Treasury And Other U.S Government Corporations And Agencies [Member]
Investments	19,060	40,652
Corporate Debt Securities [Member]
Investments	66,275	88,749
Level 1 [Member]
Total assets	80,405	69,521
Business Combination, Contingent Consideration, Liability	0	0
Derivative Liability	0	0
Financial Liabilities Fair Value Disclosure	0	0
Level 1 [Member] \| Debt Securities Issued By States Of The United States And Political Subdivisions Of The States [Member]
Investments	0	0
Level 1 [Member] \| Money Market Funds [Member]
Cash	80,405	46,867
Level 1 [Member] \| Bank Time Deposits [Member]
Cash	0	0
Level 1 [Member] \| Certificates of Deposit [Member]
Investments	0	0
Level 1 [Member] \| Equity Securities [Member]
Investments		22,654
Level 1 [Member] \| Variable Rate Demand Obligation [Member]
Investments	0
Level 1 [Member] \| Debt Securities Issued By The U.S Treasury And Other U.S Government Corporations And Agencies [Member]
Investments	0	0
Level 1 [Member] \| Corporate Debt Securities [Member]
Investments	0	0
Level 2 [Member]
Total assets	93,402	138,568
Business Combination, Contingent Consideration, Liability	0	0
Derivative Liability	1,450	1,450
Financial Liabilities Fair Value Disclosure	1,450	1,450
Level 2 [Member] \| Debt Securities Issued By States Of The United States And Political Subdivisions Of The States [Member]
Investments	5,531	6,103
Level 2 [Member] \| Money Market Funds [Member]
Cash	0	0
Level 2 [Member] \| Bank Time Deposits [Member]
Cash	73	3,004
Level 2 [Member] \| Certificates of Deposit [Member]
Investments	63	60
Level 2 [Member] \| Equity Securities [Member]
Investments		0
Level 2 [Member] \| Variable Rate Demand Obligation [Member]
Investments	2,400
Level 2 [Member] \| Debt Securities Issued By The U.S Treasury And Other U.S Government Corporations And Agencies [Member]
Investments	19,060	40,652
Level 2 [Member] \| Corporate Debt Securities [Member]
Investments	66,275	88,749
Level 3 [Member]
Total assets	0	0
Business Combination, Contingent Consideration, Liability	13,661	30,600
Derivative Liability	0	0
Financial Liabilities Fair Value Disclosure	13,661	30,600
Level 3 [Member] \| Debt Securities Issued By States Of The United States And Political Subdivisions Of The States [Member]
Investments	0	0
Level 3 [Member] \| Money Market Funds [Member]
Cash	0	0
Level 3 [Member] \| Bank Time Deposits [Member]
Cash	0	0
Level 3 [Member] \| Certificates of Deposit [Member]
Investments	0	0
Level 3 [Member] \| Equity Securities [Member]
Investments		0
Level 3 [Member] \| Variable Rate Demand Obligation [Member]
Investments	0
Level 3 [Member] \| Debt Securities Issued By The U.S Treasury And Other U.S Government Corporations And Agencies [Member]
Investments	0	0
Level 3 [Member] \| Corporate Debt Securities [Member]
Investments	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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