Finite-lived intangible asset, estimated amortization expense period.

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.

+ Details

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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

No definition available.

+ Details

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

+ Details

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 350
-SubTopic 20
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- Details

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- Details

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- Details

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Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 855,453,000	$ 790,972,000	$ 745,523,000
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	10 years
Other Identifiable Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted-average remaining life	15 years
Trust And Asset Management Acquisition [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill		$ 46,600,000
MidSouth [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 63,369,000