Consolidated Balance Sheets (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Current assets:
Allowance for trade and other receivables	$ 405	$ 163
Intangible assets accumulated amortization	$ 199,248	$ 151,735
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	47,194,023	46,894,859

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Face amount or stated value of common stock per share; generally not indicative of the fair market value per share.

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