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Borrowed Funds (Borrowed funds obligations) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Schedule of Debt [Line Items]
Borrowed funds	$ 359,776		$ 359,776		$ 344,878
Borrowed funds, Rate	1.94%		1.94%		1.65%
Securities Sold under Agreements to Repurchase [Member]
Schedule of Debt [Line Items]
Short-term Debt, Maximum Month-end Outstanding Amount	$ 40,346	$ 58,464	$ 40,346	$ 58,464
Borrowed funds	$ 39,776		$ 39,776		$ 54,878
Borrowed funds, Rate	0.10%		0.10%		0.12%
Federal Funds Purchased [Member]
Schedule of Debt [Line Items]
Short-term Debt, Maximum Month-end Outstanding Amount	$ 0	$ 3,815	$ 16,200	$ 5,965
Federal Home Loan Bank Advances [Member]
Schedule of Debt [Line Items]
Borrowed funds	$ 320,000		$ 320,000		$ 290,000
Borrowed funds, Rate	2.17%		2.17%		1.94%

X

- Definition

[Line Items] for Schedule of Debt [Table]

+ References

No definition available.

+ Details

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

+ Details

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, maximum month-end borrowings during the period.

+ References

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(19))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Details

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