Note 9 - Credit Facilities and Capital Leases (Detail) (USD $)	3 Months Ended
	Mar. 31, 2013	Apr. 30, 2013	Dec. 31, 2012	Oct. 31, 2009
Line of Credit Facility, Maximum Borrowing Capacity	$ 100,000,000	$ 150,000,000		$ 60,000,000
Debt Instrument, Covenant Description	2.50
Capital Leases Including Purchase Option	22,700,000
Capital Lease Obligations, Current	7,294,000		5,564,000
Capital Lease Obligations, Noncurrent	15,389,000		11,935,000
Capital Lease Obligations	22,511,000		17,500,000
Capital Leases, Future Minimum Payments Due	23,628,000		1,100,000
Senior Leverage Ratio [Member]
Debt Instrument, Covenant Description	4.50
Leverage Ratio [Member]
Debt Instrument, Covenant Description	4.00
Interest Coverage Ratio [Member]
Debt Instrument, Covenant Description	3.0
Tangible Net Worth [Member]
Debt Instrument, Covenant Description	80%
Positive Quarterly Net Income [Member]
Debt Instrument, Covenant Description	50%
LIBOR [Member] | Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate	3.00%
LIBOR [Member] | Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate	3.75%
Alternative Base Rate [Member] | Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate	2.00%
Alternative Base Rate [Member] | Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate	2.75%
Minimum [Member]
Standby Fee Percentage	0.825%
Maximum [Member]
Standby Fee Percentage	1.05%
Amortization of Loan Origination Fees [Member]
Interest Expense, Debt	100,000
Commitment Fees On Credit Agreement [Member]
Interest Expense, Debt	$ 300,000