Note 4 - Long-Term Debt (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 10, 2011	Mar. 31, 2013 Due March 2017 [Member]	Dec. 31, 2012 Due March 2017 [Member]
Loan Payable (in Dollars)		$ 125,000
Debt Instrument LIBOR Percentage Rate Minimum			1.50%	1.50%
Debt Instrument Periodic Payment Principal Percent	0.25%
Percentage of Company's Excess Cash Flow	25.00%
Leverage Ratio	1

The lowest stated (contractual) London Interbank Offered Rate (LIBOR) as a component of interest rate for funds borrowed under debt agreement.

No definition available.

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Principal amount of required quarterly payments stated in percentage of issued loan amount.

No definition available.

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Ratio for which the calculation be be exceeded without triggering mandatory prepayment in accordance with Term Loan.

No definition available.

Including the current and noncurrent portions, aggregate carrying value of loans payable at the time of loan issuance.

No definition available.

Percentage of excess cash flow which must be prepaid if leverage ratio level is exceeded, in accordance with Term Loan.

No definition available.

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