Note 4 - Fair Value (Details Textual) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2015	Mar. 31, 2015
Auction Rate Preferred Securities Percentage Collateralized	100.00%
Collateralized Asset Value Exceeding Value of ARPS Percentage	300.00%
Debt, Long-term and Short-term, Combined Amount	$ 54.6	$ 49.2

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant