Note 4 - Loans and Allowance for Loan Losses (Details) - Loan Portfolio by Categories - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014
Consumer:
Loans		$ 4,850,000	$ 2,740,000
Loans acquired, not covered by FDIC loss share (net of discount and allowance) (1)	[1]	2,013,816	575,980
Loans acquired, covered by FDIC loss share (net of discount and allowance) (1)	[1]	0	106,933
Total loans		4,853,094	2,736,634
Loans, Excluding Acquired Loans [Member]
Consumer:
Loans		2,839,278	2,053,721
Consumer Portfolio Segment [Member]
Consumer:
Loans		354,173	288,782
Consumer Portfolio Segment [Member] | Credit Card Receivable [Member]
Consumer:
Loans		171,701	185,380
Consumer Portfolio Segment [Member] | Other Loans [Member]
Consumer:
Loans		182,472	103,402
Consumer Portfolio Segment [Member] | Loans, Excluding Acquired Loans [Member]
Consumer:
Loans		354,173	288,782
Consumer Portfolio Segment [Member] | Loans, Excluding Acquired Loans [Member] | Credit Card Receivable [Member]
Consumer:
Loans		171,701	185,380
Consumer Portfolio Segment [Member] | Loans, Excluding Acquired Loans [Member] | Other Loans [Member]
Consumer:
Loans		182,472	103,402
Commercial Real Estate Portfolio Segment [Member]
Consumer:
Loans		1,914,409	1,352,328
Commercial Real Estate Portfolio Segment [Member] | Other Loans [Member]
Consumer:
Loans		1,037,559	714,797
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Consumer:
Loans		253,761	181,968
Commercial Real Estate Portfolio Segment [Member] | Single Family Residential Loans [Member]
Consumer:
Loans		623,089	455,563
Commercial Real Estate Portfolio Segment [Member] | Loans, Excluding Acquired Loans [Member]
Consumer:
Loans		1,914,409	1,352,328
Commercial Real Estate Portfolio Segment [Member] | Loans, Excluding Acquired Loans [Member] | Other Loans [Member]
Consumer:
Loans		1,037,559	714,797
Commercial Real Estate Portfolio Segment [Member] | Loans, Excluding Acquired Loans [Member] | Construction Loans [Member]
Consumer:
Loans		253,761	181,968
Commercial Real Estate Portfolio Segment [Member] | Loans, Excluding Acquired Loans [Member] | Single Family Residential Loans [Member]
Consumer:
Loans		623,089	455,563
Commercial Portfolio Segment [Member]
Consumer:
Loans		564,679	407,478
Commercial Portfolio Segment [Member] | Commercial Loans [Member]
Consumer:
Loans		394,422	291,820
Commercial Portfolio Segment [Member] | Agricultural Loans [Member]
Consumer:
Loans		170,257	115,658
Commercial Portfolio Segment [Member] | Loans, Excluding Acquired Loans [Member]
Consumer:
Loans		564,679	407,478
Commercial Portfolio Segment [Member] | Loans, Excluding Acquired Loans [Member] | Commercial Loans [Member]
Consumer:
Loans		394,422	291,820
Commercial Portfolio Segment [Member] | Loans, Excluding Acquired Loans [Member] | Agricultural Loans [Member]
Consumer:
Loans		170,257	115,658
Unallocated Financing Receivables [Member]
Consumer:
Loans		6,017	5,133
Unallocated Financing Receivables [Member] | Loans, Excluding Acquired Loans [Member]
Consumer:
Loans		$ 6,017	$ 5,133

[1] See Note 5, Loans Acquired, for segregation of loans acquired by loan class. In September 2015 the Company entered into an agreement withthe FDIC to terminate all loss sharing agreements.