Note 7 - Equity-Based Compensation (Detail) - Stock Option Activity (USD $)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Outstanding at January 1 (in Shares)	1,198,516	1,167,640	1,032,773
Outstanding at January 1	$ 18.42	$ 17.71	$ 19.18
Granted (in Shares)	225,505	215,722	340,609
Granted	$ 26.92	$ 22.87	$ 12.83
Exercised (in Shares)	(128,052)	(132,485)	(74,524)
Exercised	$ 16.48	$ 17.16	$ 15.30
Forfeited/expired (in Shares)	(188,257)	(52,361)	(131,218)
Forfeited/expired	$ 26.62	$ 25.53	$ 18.20
Outstanding at December 31 (in Shares)	1,107,712	1,198,516	1,167,640
Outstanding at December 31	$ 18.98	$ 18.42	$ 17.71
Exercisable at December 31 (in Shares)	690,449	678,649	633,789
Exercisable at December 31	$ 16.82	$ 19.37	$ 21.30

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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