Note 9 - Commitments and Financial Instruments with Off-Balance-Sheet Risk (Details) - Changes in allowance for indemnifications losses (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Changes in allowance for indemnifications losses [Abstract]
Allowance, beginning of period	$ 2,082	$ 1,827	$ 2,092	$ 1,702
Provision for indemnification losses	150	330	375	455
Payments	0	(500)	(235)	(500)
Allowance, end of period	$ 2,232	$ 1,657	$ 2,232	$ 1,657

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Amount of loss contingency liability.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

+ Details

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- Definition

Amount of payments made reducing loss contingency liability.

+ References

+ Details

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- Definition

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

+ References

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