Note 8 - Loans and the Allowance for Loan Losses (Detail) - Impaired Loans (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended	18 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Dec. 31, 2011
With No Related Allowance Recorded [Member] \| Commercial Loans [Member]
Recorded Balance With No Related Allowance Recorded	$ 2,933	$ 9,737	$ 2,933	$ 9,737	$ 2,933	$ 1,300
Unpaid Principal Balance With No Related Allowance Recorded		11,450		11,450		1,631
Specific Allowance With No Related Allowance Recorded	3,323	0	3,323	0	3,323	0
Average Investment in Impaired Loans With No Related Allowance Recorded	3,317	9,922	46	9,812	5,593
Interest Income Recognized With No Related Allowance Recorded	17	27	61	55	7,477
Interest Income Recognized Cash Basis With No Related Allowance Recorded	17		3,209
Specific Allowance With An Allowance Recorded	3,323	0	3,323	0	3,323	0
Total:
Specific Allowance	3,323	0	3,323	0	3,323	0
With No Related Allowance Recorded [Member] \| Commercial Real Estate Loans [Member]
Recorded Balance With No Related Allowance Recorded	25,140	25,852	25,140	25,852	25,140	33,494
Unpaid Principal Balance With No Related Allowance Recorded		34,249		34,249		55,356
Specific Allowance With No Related Allowance Recorded	26,502	0	26,502	0	26,502	0
Average Investment in Impaired Loans With No Related Allowance Recorded	25,823	29,481	230	19,378	24,916
Interest Income Recognized With No Related Allowance Recorded	141	13	238	36	721
Interest Income Recognized Cash Basis With No Related Allowance Recorded	136		38,660		861
Specific Allowance With An Allowance Recorded	26,502	0	26,502	0	26,502	0
Total:
Specific Allowance	26,502	0	26,502	0	26,502	0
With No Related Allowance Recorded [Member] \| Commercial Real Estate Development [Member]
Recorded Balance With No Related Allowance Recorded	9,767	25,631	9,767	25,631	9,767	23,970
Unpaid Principal Balance With No Related Allowance Recorded		42,877		42,877		46,275
Specific Allowance With No Related Allowance Recorded	9,922	0	9,922	0	9,922	0
Average Investment in Impaired Loans With No Related Allowance Recorded	9,907	29,627	71	26,163	25,961
Interest Income Recognized With No Related Allowance Recorded	34	46	81	96	323
Interest Income Recognized Cash Basis With No Related Allowance Recorded	31		18,104		371
Specific Allowance With An Allowance Recorded	9,922	0	9,922	0	9,922	0
Total:
Specific Allowance	9,922	0	9,922	0	9,922	0
With No Related Allowance Recorded [Member] \| Residential Real Estate Loans [Member]
Recorded Balance With No Related Allowance Recorded	4,013	6,374	4,013	6,374	4,013	7,305
Unpaid Principal Balance With No Related Allowance Recorded		7,588		7,588		9,773
Specific Allowance With No Related Allowance Recorded	4,228	0	4,228	0	4,228	0
Average Investment in Impaired Loans With No Related Allowance Recorded	4,163	6,846	43	5,527	5,993
Interest Income Recognized With No Related Allowance Recorded	23	4	46	15	173
Interest Income Recognized Cash Basis With No Related Allowance Recorded	17		5,254		205
Specific Allowance With An Allowance Recorded	4,228	0	4,228	0	4,228	0
Total:
Specific Allowance	4,228	0	4,228	0	4,228	0
With No Related Allowance Recorded [Member] \| Consumer Loans [Member]
Recorded Balance With No Related Allowance Recorded	400	657	400	657	400	1,119
Unpaid Principal Balance With No Related Allowance Recorded		783		783		1,359
Specific Allowance With No Related Allowance Recorded	466	0	466	0	466	0
Average Investment in Impaired Loans With No Related Allowance Recorded	446	731	11	329	559
Interest Income Recognized With No Related Allowance Recorded	5	3	11	8	50
Interest Income Recognized Cash Basis With No Related Allowance Recorded	5		1,057		54
Specific Allowance With An Allowance Recorded	466	0	466	0	466	0
Total:
Specific Allowance	466	0	466	0	466	0
With An Allowance Recorded [Member] \| Commercial Loans [Member]
Specific Allowance With No Related Allowance Recorded	1,589	1,879	1,589	1,879	1,589	2,632
Recorded Balance With An Allowance Recorded	1,479	3,562	1,479	3,562	1,479	3,566
Unpaid Principal Balance With An Allowance Recorded	1,139	3,930	1,139	3,930	1,139	3,566
Specific Allowance With An Allowance Recorded	1,589	1,879	1,589	1,879	1,589	2,632
Average Investment in Impaired Loans With An Allowance Recorded	1,578	3,691	15	2,735	2,737
Interest Income Recognized With An Allowance Recorded	8	2	22	8	148
Interest Income Recognized Cash Basis With An Allowance Recorded	5		1,510		165
Total:
Specific Allowance	1,589	1,879	1,589	1,879	1,589	2,632
With An Allowance Recorded [Member] \| Commercial Real Estate Loans [Member]
Specific Allowance With No Related Allowance Recorded	13,167	1,169	13,167	1,169	13,167	13,398
Recorded Balance With An Allowance Recorded	11,996	7,145	11,996	7,145	11,996	8,666
Unpaid Principal Balance With An Allowance Recorded	1,229	7,351	1,229	7,351	1,229	86,662,566
Specific Allowance With An Allowance Recorded	13,167	1,169	13,167	1,169	13,167	13,398
Average Investment in Impaired Loans With An Allowance Recorded	12,157	7,159	16	12,638	424
Interest Income Recognized With An Allowance Recorded	15	85	33	181	478
Interest Income Recognized Cash Basis With An Allowance Recorded	15		16,981
Total:
Specific Allowance	13,167	1,169	13,167	1,169	13,167	13,398
With An Allowance Recorded [Member] \| Commercial Real Estate Development [Member]
Specific Allowance With No Related Allowance Recorded	16,279	4,722	16,279	4,722	16,279	20,241
Recorded Balance With An Allowance Recorded	10,627	14,714	10,627	14,714	10,627	21,974
Unpaid Principal Balance With An Allowance Recorded	983	15,294	983	15,294	983	219,748,215
Specific Allowance With An Allowance Recorded	16,279	4,722	16,279	4,722	16,279	20,241
Average Investment in Impaired Loans With An Allowance Recorded	16,022	14,799	11	16,611	13,351,420
Interest Income Recognized With An Allowance Recorded	7	73	11	151
Interest Income Recognized Cash Basis With An Allowance Recorded	7		27,678
Total:
Specific Allowance	16,279	4,722	16,279	4,722	16,279	20,241
With An Allowance Recorded [Member] \| Residential Real Estate Loans [Member]
Specific Allowance With No Related Allowance Recorded	5,697	757	5,697	757	5,697	3,930,157
Recorded Balance With An Allowance Recorded	5,533	3,525	5,533	3,525	5,533	3,986
Unpaid Principal Balance With An Allowance Recorded	1,491	3,615	1,491	3,615	1,491	43,651,584
Specific Allowance With An Allowance Recorded	5,697	757	5,697	757	5,697	3,930,157
Average Investment in Impaired Loans With An Allowance Recorded	5,540	3,548	102	3,699	172
Interest Income Recognized With An Allowance Recorded	34	11	92	36
Interest Income Recognized Cash Basis With An Allowance Recorded	23		6,121
Total:
Specific Allowance	5,697	757	5,697	757	5,697	3,930,157
With An Allowance Recorded [Member] \| Consumer Loans [Member]
Specific Allowance With No Related Allowance Recorded	691	298	691	298	691	219
Recorded Balance With An Allowance Recorded	667	409	667	409	667	561
Unpaid Principal Balance With An Allowance Recorded	153	409	153	409	153	561
Specific Allowance With An Allowance Recorded	691	298	691	298	691	219
Average Investment in Impaired Loans With An Allowance Recorded	688	412	16	589	665
Interest Income Recognized With An Allowance Recorded	8	3	15	6	23
Interest Income Recognized Cash Basis With An Allowance Recorded	5		971		24
Total:
Specific Allowance	691	298	691	298	691	219
Commercial Loans [Member]
Specific Allowance With No Related Allowance Recorded	70,782	7,770	70,782	7,770	70,782	13,413
Specific Allowance With An Allowance Recorded	70,782	7,770	70,782	7,770	70,782	13,413
Total:
Recorded Balance	61,942	86,641	61,942	86,641	61,942	92,970
Unpaid Principal Balance	3,351	115,151	3,351	115,151	3,351	137,468
Specific Allowance	70,782	7,770	70,782	7,770	70,782	13,413
Average Investment in Impaired Loans	68,796	94,677	389	87,336	92,845
Interest Income Recognized	222	246	446	527	3,025
Interest Income Recognized Cash Basis	211		106,142		3,372
Consumer Loans [Member]
Specific Allowance With No Related Allowance Recorded	1,157	298	1,157	298	1,157	219
Specific Allowance With An Allowance Recorded	1,157	298	1,157	298	1,157	219
Total:
Recorded Balance	1,067	1,066	1,067	1,066	1,067	1,680
Unpaid Principal Balance	153	1,192	153	1,192	153	1,920
Specific Allowance	1,157	298	1,157	298	1,157	219
Average Investment in Impaired Loans	1,134	1,143	27	917	1,224
Interest Income Recognized	13	6	26	14	73
Interest Income Recognized Cash Basis	10		2,028		78
Residential Loans [Member]
Specific Allowance With No Related Allowance Recorded	9,925	757	9,925	757	9,925	1,584
Specific Allowance With An Allowance Recorded	9,925	757	9,925	757	9,925	1,584
Total:
Recorded Balance	9,546	9,899	9,546	9,899	9,546	11,291
Unpaid Principal Balance	1,491	11,203	1,491	11,203	1,491	14,138
Specific Allowance	9,925	757	9,925	757	9,925	1,584
Average Investment in Impaired Loans	9,703	10,394	145	9,226	9,923
Interest Income Recognized	57	15	138	51	330
Interest Income Recognized Cash Basis	$ 40		$ 11,375		$ 377

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953550-111524

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