Note 20 - Revenue From Contracts With Customers (Details Textual) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Contract with Customer, Asset, Net, Total	$ 0		$ 0
Contract with Customer, Liability, Total	0		0
Contract with Customer, Liability, Revenue Recognized			0
Safety Box Deposit Fees [Member] \| Other Income [Member]
Revenue from Contract with Customer, Including Assessed Tax	46,000	$ 43,000	137,000	$ 128,000
Fiduciary and Trust [Member]
Revenue from Contract with Customer, Including Assessed Tax	5,380,000	$ 5,025,000	16,224,000	$ 15,272,000
Accrued Fees and Other Revenue Receivable	$ 2,100,000		$ 2,100,000		$ 2,200,000

For an unclassified balance sheet, the amount of fees and other revenue, excluding investment income receivable, earned but not yet received, which were recognized in conformity with revenue recognition criteria based on estimates or specific contractual terms.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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- Definition

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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