Derivative Financial Instruments (Narrative) (Details) $ in Thousands	Mar. 31, 2021 USD ($) derivative_instrument	Dec. 31, 2020 USD ($) derivative_instrument
Interest rate swaps [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 60,000	$ 60,000
Interest rate swaps with customers [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	983,619	991,002
Mirror swaps with counterparties [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	983,619	991,002
Risk participation-in agreement [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	107,493	92,717
Interest rate lock commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	155,800	167,671
Forward sale commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	290,989	279,653
Derivatives Designated as Cash Flow Hedging Instruments [Member] \| Interest rate swaps [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 60,000	$ 60,000
Number of instruments held \| derivative_instrument	2	2
Not Designated as Hedging Instrument [Member] \| Interest rate swaps with customers [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 983,600	$ 991,000
Not Designated as Hedging Instrument [Member] \| Mirror swaps with counterparties [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	983,600	991,000
Not Designated as Hedging Instrument [Member] \| Risk participation-out agreement [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	62,000	61,600
Not Designated as Hedging Instrument [Member] \| Risk participation-in agreement [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 107,500	$ 92,700

Nominal or face amount used to calculate payment on derivative.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

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+ References

No definition available.

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