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Note 3 - Loans and Allowance for Loan Losses - Retail Credit Exposure (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Loans	$ 2,697,417,000	$ 2,558,552,000
Retail Portfolio Segment [Member]
Loans	391,310,000	354,984,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Loans	89,545,000	100,425,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Loans	301,765,000	254,559,000
Originated Loan [Member]
Loans	2,383,104,000	2,169,957,000
Originated Loan [Member] | Retail Portfolio Segment [Member]
Loans	292,628,000	235,729,000
Originated Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Loans	67,412,000	69,675,000
Originated Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Loans	225,216,000	166,054,000
Acquired Loan [Member]
Loans	314,313,000	388,595,000
Acquired Loan [Member] | Retail Portfolio Segment [Member]
Loans	98,682,000	119,255,000
Acquired Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Loans	22,133,000	30,750,000
Acquired Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Loans	$ 76,549,000	$ 88,505,000

X

- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

+ Details

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Period Type:	instant

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