Note 8 - Fair Value Measurements (Details) - Fair Values Of Company's Financial Instruments (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Assets
Carrying Value	$ 8,013	$ 7,439	$ 6,780
Fair Value	8,013	7,439
Carrying Value	3,844	7,852	4,173
Fair Value	3,844	7,852	4,173
Carrying Value	208,522	324,043	46,752
Fair Value	208,522	324,043	46,752
Carrying Value	355,830	299,820	296,363
Fair Value	355,830	299,820	296,363
Carrying Value	11,246	10,694
Fair Value	11,246	10,694
Carrying Value	39,206	226,923	171,241
Fair Value	39,206	226,923
Carrying Value	2,796,840	2,493,095	2,397,669
Fair Value	2,832,774	2,515,409
Carrying Value	29,555	14,135	14,036
Fair Value	29,555	14,135	14,036
Other earning assets	11,184
Other earning assets	11,184
Liabilities
Carrying Value	2,984,059	2,897,222	2,514,989
Carrying Value	121,566	140,638
Fair Value	123,186	142,765
Fair Value, Inputs, Level 1 [Member]
Assets
Carrying Value	151	112
Fair Value	151	112
Fair Value, Inputs, Level 2 [Member]
Assets
Fair Value	8,013	7,439
Carrying Value	3,844	7,852
Fair Value	3,844	7,852
Carrying Value	208,522	324,043
Fair Value	208,522	324,043
Carrying Value	355,444	299,478
Fair Value	355,444	299,478
Fair Value	11,246	10,694
Fair Value	39,206	226,923
Fair Value	17,194	29,021
Carrying Value	29,555	14,135
Fair Value	29,555	14,135
Other earning assets	11,184
Other earning assets	11,184
Liabilities
Fair Value	123,186	142,765
Fair Value, Inputs, Level 2 [Member] \| Noninterest-bearing Deposits [Member]
Liabilities
Fair Value	898,831	881,390
Fair Value, Inputs, Level 2 [Member] \| Interest-bearing Deposits [Member]
Liabilities
Fair Value	2,085,185	2,017,623
Fair Value, Inputs, Level 3 [Member]
Assets
Carrying Value	235	230
Fair Value	235	230
Fair Value	2,815,580	2,486,388
Noninterest-bearing Deposits [Member]
Liabilities
Carrying Value	898,831	881,390
Fair Value	898,831	881,390
Interest-bearing Deposits [Member]
Liabilities
Carrying Value	2,085,228	2,015,832
Fair Value	$ 2,085,185	$ 2,017,623

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

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-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

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- Definition

The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

+ References

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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- Definition

For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

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-Name Accounting Standards Codification

-Glossary Cash Equivalents

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.1)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1, 2, 3

-Article 9

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- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

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- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

No definition available.

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- Definition

The amount outstanding of funds lent to other depository institutions, securities brokers, or securities dealers in the form of Federal Funds sold; for example, immediately available funds lent under agreements or contracts that mature in one business day or roll over under a continuing contract, regardless of the nature of the transaction or the collateral involved, excluding overnight lending for commercial and industrial purposes. Also include Federal Funds sold under agreements to resell on a gross basis, excluding (1) sales of term Federal Funds, (2) due bills representing purchases of securities or other assets by the reporting bank that have not yet been delivered and similar instruments, (3) resale agreements that mature in more than one business day involving assets other than securities, and (4) yield maintenance dollar repurchase agreements.

+ References

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- Definition

For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.2)

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-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 2

-Article 9

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5074-111524

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-Topic 310

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-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

No definition available.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Glossary Loan

-URI http://asc.fasb.org/extlink&oid=6517073

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- Definition

Amount of loans held for sale, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 45

-Paragraph 2

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-Number 210

-Section 03

-Paragraph 7

-Subparagraph a

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-Topic 942

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-Name Accounting Standards Codification

-Topic 948

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-Section 30

-Paragraph 1

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- Definition

The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

+ References

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- Definition

The amount of other interest earning assets not otherwise specified in the taxonomy.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Topic 942

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-Paragraph 1

-Subparagraph (SX 210.9-03.6(a)(3),7(a)(7))

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- Definition

Fair value portion of other liabilities.

+ References

No definition available.

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- Definition

Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

+ References

No definition available.

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- Definition

The aggregate value of all restricted investments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 320

-Section S99

-Paragraph 4

-Subparagraph (SX 210.12-12C.9(c))

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