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Fair Values of Financial Instruments, Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financial assets [Abstract]
HTM securities	$ 636,827	$ 641,262
Carrying Amount [Member] | Level 1 [Member]
Financial liabilities [Abstract]
Subordinated debt	100,000	0
Carrying Amount [Member] | Level 2 [Member]
Financial assets [Abstract]
HTM securities	616,560	630,074
Financial liabilities [Abstract]
Time deposits	633,479	861,193
Long-term debt	39,097	64,211
Junior subordinated debt	101,196	101,196
Carrying Amount [Member] | Level 3 [Member]
Financial assets [Abstract]
Net loans	7,390,004	7,074,864
Estimated Fair Value [Member] | Level 1 [Member]
Financial liabilities [Abstract]
Subordinated debt	103,277	0
Estimated Fair Value [Member] | Level 2 [Member]
Financial assets [Abstract]
HTM securities	636,827	641,262
Financial liabilities [Abstract]
Time deposits	638,721	858,085
Long-term debt	39,820	64,373
Junior subordinated debt	108,926	105,694
Estimated Fair Value [Member] | Level 3 [Member]
Financial assets [Abstract]
Net loans	$ 7,530,033	$ 6,999,690

X

- Definition

Fair value of junior subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

+ References

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- Definition

Fair value portion of time deposit liabilities, including certificates of deposit.

+ References

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

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- Definition

Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
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-Subparagraph (SX 210.9-03(6))
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-Topic 320
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-Paragraph 5A
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-URI http://asc.fasb.org/extlink&oid=121645371&loc=SL120269820-111563

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

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