Note 4 - Debt and Equity Securities (Detail) - Available for sale securities with gross unrealized losses and their fair value: (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Fair Value	$ 241,302	$ 89,303
Unrealized Losses	7,537	7,772
Fair Value, Less than 12 months	211,941	60,764
Unrealized Losses, Less than 12 months	1,638	320
Fair Value, 12 months or more	29,361	28,539
Unrealized Losses, 12 months or more	5,899	7,452
Corporate Debt Securities [Member]
Fair Value	9,981
Unrealized Losses	19
Fair Value, Less than 12 months	9,981
Unrealized Losses, Less than 12 months	19
Municipal [Member]
Fair Value	21,666	9,782
Unrealized Losses	330	83
Fair Value, Less than 12 months	21,666	9,782
Unrealized Losses, Less than 12 months	330	83
Other Debt Obligations [Member]
Fair Value	5,600	5,064
Unrealized Losses	3,962	4,499
Fair Value, 12 months or more	5,600	5,064
Unrealized Losses, 12 months or more	3,962	4,499
Available For Sale Securities Excluding Mortgage Backed Securities [Member]
Fair Value	37,247	14,846
Unrealized Losses	4,311	4,582
Fair Value, Less than 12 months	31,647	9,782
Unrealized Losses, Less than 12 months	349	83
Fair Value, 12 months or more	5,600	5,064
Unrealized Losses, 12 months or more	3,962	4,499
REMIC And CMO [Member]
Fair Value	130,532	64,126
Unrealized Losses	2,497	3,108
Fair Value, Less than 12 months	106,771	40,651
Unrealized Losses, Less than 12 months	560	155
Fair Value, 12 months or more	23,761	23,475
Unrealized Losses, 12 months or more	1,937	2,953
FNMA [Member]
Fair Value	73,523	10,331
Unrealized Losses	729	82
Fair Value, Less than 12 months	73,523	10,331
Unrealized Losses, Less than 12 months	729	82
Collateralized Mortgage Backed Securities [Member]
Fair Value	204,055	74,457
Unrealized Losses	3,226	3,190
Fair Value, Less than 12 months	180,294	50,982
Unrealized Losses, Less than 12 months	1,289	237
Fair Value, 12 months or more	23,761	23,475
Unrealized Losses, 12 months or more	$ 1,937	$ 2,953