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Borrowed Funds (Borrowed funds obligations) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Schedule of Debt [Line Items]
Borrowed funds	$ 311,684		$ 340,299
Borrowed funds, Rate	2.03%		1.95%
Securities Sold under Agreements to Repurchase [Member]
Schedule of Debt [Line Items]
Short-term Debt, Maximum Month-end Outstanding Amount	$ 37,441	$ 38,967
Borrowed funds	$ 29,824		$ 40,299
Borrowed funds, Rate	0.09%		0.11%
Federal Funds Purchased [Member]
Schedule of Debt [Line Items]
Short-term Debt, Maximum Month-end Outstanding Amount	$ 1,860	$ 10,200
Borrowed funds	$ 1,860		$ 0
Borrowed funds, Rate	2.64%		0.00%
Federal Home Loan Bank Advances [Member]
Schedule of Debt [Line Items]
Borrowed funds	$ 280,000		$ 300,000
Borrowed funds, Rate	2.24%		2.20%

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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- Details

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