Note 5 - Loans (Detail) - Non-accrual Troubled Debt Restructurings (USD $)	Dec. 31, 2012	Dec. 31, 2011
Non-accrual TDRs	$ 144,695,000	$ 120,016,000
Non Accruing Troubled Debt Restructuring Member | Interest Deferral [Member] | Commercial Mortgage Loans [Member]
Non-accrual TDRs	1,685,000	2,633,000
Non Accruing Troubled Debt Restructuring Member | Interest Deferral [Member] | Residential Mortgage Loans [Member]
Non-accrual TDRs	275,000	311,000
Non Accruing Troubled Debt Restructuring Member | Interest Deferral [Member]
Non-accrual TDRs	1,960,000	2,944,000
Non Accruing Troubled Debt Restructuring Member | Real Estate Construction Loans [Member] | Commercial Loans Member
Non-accrual TDRs	912,000	616,000
Non Accruing Troubled Debt Restructuring Member | Real Estate Construction Loans [Member] | Real Estate Construction Loans [Member]
Non-accrual TDRs	16,767,000	13,579,000
Non Accruing Troubled Debt Restructuring Member | Real Estate Construction Loans [Member] | Commercial Mortgage Loans [Member]
Non-accrual TDRs	2,817,000	9,727,000
Non Accruing Troubled Debt Restructuring Member | Real Estate Construction Loans [Member] | Residential Mortgage Loans [Member]
Non-accrual TDRs	2,010,000	2,427,000
Non Accruing Troubled Debt Restructuring Member | Real Estate Construction Loans [Member]
Non-accrual TDRs	22,506,000	26,349,000
Non Accruing Troubled Debt Restructuring Member | Rate Reduction [Member] | Commercial Loans Member
Non-accrual TDRs		1,859,000
Non Accruing Troubled Debt Restructuring Member | Rate Reduction [Member] | Real Estate Construction Loans [Member]
Non-accrual TDRs	9,579,000	12,376,000
Non Accruing Troubled Debt Restructuring Member | Rate Reduction [Member] | Commercial Mortgage Loans [Member]
Non-accrual TDRs	5,746,000
Non Accruing Troubled Debt Restructuring Member | Rate Reduction [Member] | Residential Mortgage Loans [Member]
Non-accrual TDRs	586,000	449,000
Non Accruing Troubled Debt Restructuring Member | Rate Reduction [Member]
Non-accrual TDRs	15,911,000	14,684,000
Non Accruing Troubled Debt Restructuring Member | Rate Reduction and Forgiveness of Principal [Member] | Commercial Loans Member
Non-accrual TDRs	1,518,000	1,506,000
Non Accruing Troubled Debt Restructuring Member | Rate Reduction and Forgiveness of Principal [Member]
Non-accrual TDRs	1,518,000	1,506,000
Non Accruing Troubled Debt Restructuring Member | Rate Reduction and Payment Deferral [Member] | Commercial Mortgage Loans [Member]
Non-accrual TDRs	5,076,000	5,076,000
Non Accruing Troubled Debt Restructuring Member | Rate Reduction and Payment Deferral [Member] | Residential Mortgage Loans [Member]
Non-accrual TDRs	760,000	311,000
Non Accruing Troubled Debt Restructuring Member | Rate Reduction and Payment Deferral [Member]
Non-accrual TDRs	5,836,000	5,387,000
Non Accruing Troubled Debt Restructuring Member | Commercial Loans Member
Non-accrual TDRs	2,430,000	3,981,000
Non Accruing Troubled Debt Restructuring Member | Real Estate Construction Loans [Member]
Non-accrual TDRs	26,346,000	25,955,000
Non Accruing Troubled Debt Restructuring Member | Commercial Mortgage Loans [Member]
Non-accrual TDRs	15,324,000	17,436,000
Non Accruing Troubled Debt Restructuring Member | Residential Mortgage Loans [Member]
Non-accrual TDRs	3,631,000	3,498,000
Non Accruing Troubled Debt Restructuring Member
Non-accrual TDRs	47,731,000	50,870,000
Commercial Loans Member
Non-accrual TDRs	3,964,000	15,120,000
Real Estate Construction Loans [Member]
Non-accrual TDRs	5,834,000	32,255,000
Commercial Mortgage Loans [Member]
Non-accrual TDRs	130,181,000	69,273,000
Residential Mortgage Loans [Member]
Non-accrual TDRs	$ 4,716,000	$ 3,368,000