Note 2 - Acquisitions (Details) (USD $)	12 Months Ended	1 Months Ended	0 Months Ended		1 Months Ended	0 Months Ended	11 Months Ended
	Dec. 31, 2014	Oct. 19, 2012	Aug. 31, 2014	May 06, 2014	Nov. 25, 2013	Sep. 14, 2012	Nov. 24, 2013	Dec. 31, 2013	Oct. 14, 2012	Aug. 29, 2014
Note 2 - Acquisitions (Details) [Line Items]
Deposits	$ 3,860,718,000							$ 3,697,567,000
Goodwill	108,095,000							78,529,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	35.00%
Time Deposits	965,187,000							1,116,511,000
Payable to FDIC [Member] | Truman [Member]
Note 2 - Acquisitions (Details) [Line Items]
Accounts Payable, Other		1,300,000
Fair Value Adjustments [Member] | Delta Trust [Member]
Note 2 - Acquisitions (Details) [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets			(3,406,000)
Goodwill			(822,000)
			(15,149,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities			(37,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment			(433,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets Noncurrent			558,000
Fair Value Adjustments [Member] | Metropolitan [Member]
Note 2 - Acquisitions (Details) [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets					(25,515,000)
Goodwill					17,900,000
					(37,467,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities					(2,259,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment					(22,575,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets Noncurrent					30,699,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable					77,000
Fair Value Adjustments [Member] | Truman [Member]
Note 2 - Acquisitions (Details) [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets									(26,551,000)
									(15,965,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable									357,000
Fair Value Adjustments [Member] | Excel [Member]
Note 2 - Acquisitions (Details) [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets		(17,443,000)
		(5,376,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable		706,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, FHLB Borrowings		183,000
Bank Time Deposits [Member]
Note 2 - Acquisitions (Details) [Line Items]
Assets, Fair Value Adjustment		0
Delta Trust [Member]
Note 2 - Acquisitions (Details) [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in Shares)			1,629,515
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned										65,000,000
Payments to Acquire Businesses, Gross			2,400,000
Number of Bank Branches			9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets			417,386,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets			312,000,000
Deposits			355,000,000
Goodwill			29,022,000
Business Combination, Percentage of Fair Value Adjustment, Deferred Tax Asset			39.225%
			311,680,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities			62,373,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment			3,972,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets Noncurrent			2,417,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents			13,739,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable			1,528,000
Metropolitan [Member]
Note 2 - Acquisitions (Details) [Line Items]
Payments to Acquire Businesses, Gross					53,600,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets					919,340,000
Deposits					838,000,000
Goodwill					17,924,000
Business Combination, Acquisition Related Costs				6,600,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets, Net					884,000,000
					457,372,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities					232,901,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment					52,178,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	39.225%
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets Noncurrent	34,000,000				30,699,000		34,000,000
Time Deposits					512,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents					12,026,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable					9,520,000
Truman [Member] | Cash Received From FDIC [Member]
Note 2 - Acquisitions (Details) [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents						10,500,000
Truman [Member] | Real Estate Banking Facilities Furniture and Equipment [Member]
Note 2 - Acquisitions (Details) [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	1,400,000
Truman [Member]
Note 2 - Acquisitions (Details) [Line Items]
Number of Bank Branches						4
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets									253,174,000
									73,395,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities									23,540,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment									1,390,000
Business Combination, Bargain Purchase, Gain Recognized, Amount						1,100,000
Payments for Merger Related Costs						815,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents									22,467,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable									760,000
Excel [Member] | Cash Received From FDIC [Member]
Note 2 - Acquisitions (Details) [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable		13,800,000
Excel [Member] | Real Estate Banking Facilities Furniture and Equipment [Member]
Note 2 - Acquisitions (Details) [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	2,600,000
Excel [Member]
Note 2 - Acquisitions (Details) [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets		180,536,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets						1,100,000
		21,152,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities		8,583,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		2,582,000
Business Combination, Bargain Purchase, Gain Recognized, Amount						2,300,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents		18,622,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable		1,132,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, FHLB Borrowings		8,193,000
Metropolitan [Member]
Note 2 - Acquisitions (Details) [Line Items]
Number of Bank Branches							45
Operating Loss Carryforwards	$ 72,800,000						$ 72,800,000