Note 8 - Fair Value Measurements (Details) - Fair Values of Company's Financial Instruments (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013
Assets
Carrying Value	$ 8,982	$ 9,577	$ 7,123
Fair Value	8,982	9,577
Carrying Value	8,468	5,695	5,811
Fair Value	8,468	5,695	5,811
Carrying Value	213,501	291,688	257,957
Fair Value	213,501	291,688	257,957
Carrying Value	387,790	378,133	318,431
Fair Value	387,790	378,133	318,431
Carrying Value	10,599	11,272
Fair Value	10,599	11,272
Carrying Value	21,862	42,030	132,698
Fair Value	21,862	42,030
Carrying Value	3,063,975	2,945,158	2,548,024
Fair Value	3,097,497	2,979,180
Carrying Value	40,052	39,738	14,229
Fair Value	40,052	39,738	14,229
Carrying Value	11,267	11,227
Fair Value	11,267	11,227
Liabilities
Carrying Value	3,273,689	3,225,414	2,812,930
Carrying Value	105,737	119,771
Fair Value	106,712	120,764
Fair Value, Inputs, Level 1 [Member]
Assets
Carrying Value	198	165
Fair Value	198	165
Fair Value, Inputs, Level 2 [Member]
Assets
Fair Value	8,982	9,577
Carrying Value	8,468	5,695
Fair Value	8,468	5,695
Carrying Value	213,501	291,688
Fair Value	213,501	291,688
Carrying Value	387,373	377,749
Fair Value	387,373	377,749
Fair Value	10,599	11,272
Fair Value	21,862	42,030
Fair Value	11,186	14,249
Carrying Value	40,052	39,738
Fair Value	40,052	39,738
Carrying Value	11,267	11,227
Fair Value	11,267	11,227
Liabilities
Fair Value	106,712	120,764
Fair Value, Inputs, Level 2 [Member] \| Noninterest-bearing Deposits [Member]
Liabilities
Fair Value	886,623	849,409
Fair Value, Inputs, Level 2 [Member] \| Interest-bearing Deposits [Member]
Liabilities
Fair Value	2,386,650	2,375,861
Fair Value, Inputs, Level 3 [Member]
Assets
Carrying Value	219	219
Fair Value	219	219
Fair Value	3,086,311	2,964,931
Noninterest-bearing Deposits [Member]
Liabilities
Carrying Value	886,623	849,409
Fair Value	886,623	849,409
Interest-bearing Deposits [Member]
Liabilities
Carrying Value	2,387,066	2,376,005
Fair Value	$ 2,386,650	$ 2,375,861

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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

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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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-Publisher SEC

-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

-SubTopic 10

-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

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

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-Number 210

-Section 03

-Paragraph 7

-Subparagraph a

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-Publisher FASB

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-Topic 942

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-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-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

-Paragraph 7

-Subparagraph a

-Article 9

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-Publisher FASB

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-Topic 942

-SubTopic 210

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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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