Finite-lived intangible asset, estimated amortization expense period.

No definition available.

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- Definition

Percentage of fair value valuation of reporting unit excess of net book value.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 926
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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($)		12 Months Ended
	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Sep. 21, 2019
Finite-Lived Intangible Assets [Line Items]
Goodwill		$ 855,453,000	$ 855,453,000	$ 790,972,000
Percentage of fair value of reporting unit in excess of net book value	17.00%
Goodwill impairment charges		$ 0	0	$ 0
Estimated amortization expense succeeding period		5 years
Core Deposit Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted-average remaining life		9 years
Other Identifiable Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted-average remaining life		14 years
MidSouth [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill		$ 63,369,000	$ 63,400,000		$ 63,400,000