Note 11 - Derivative Financial Instruments (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013
Junior Subordinated Notes, Portion Exposed To Rising Interest Rates	$ 18.0
Junior Subordinated Notes, Contractual Value	61.9
Notional Amount of Interest Rate Derivative Instruments Not Designated as Hedging Instruments	118.0
Notional Amount of Interest Rate Cash Flow Hedge Derivatives	$ 4.3

Aggregate notional amount of all interest rate derivatives not designated as hedging instruments. Notional amount refers to the monetary amount specified in the interest rate derivative contract.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959

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