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

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
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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

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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=120320667&loc=SL49117168-202975

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

+ Details

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- Definition

Amount of increase (decrease) 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 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

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- Details

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- Details

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Goodwill and Other Intangible Assets - Textual (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Mar. 31, 2020	Jun. 30, 2020	Dec. 31, 2019	Oct. 31, 2019	Oct. 30, 2019	Apr. 12, 2019
Finite-Lived Intangible Assets [Line Items]
Goodwill		$ 1,064,765	$ 1,055,520
Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life		10 years
Maximum
Finite-Lived Intangible Assets [Line Items]
Useful life		15 years
Core Deposit Premium \| Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life		10 years
Core Deposit Premium \| Maximum
Finite-Lived Intangible Assets [Line Items]
Useful life		15 years
Landrum Company
Finite-Lived Intangible Assets [Line Items]
Goodwill			131,300	$ 140,584	$ 407
Goodwill increase	$ 9,200
Reliance Bancshares, Inc.
Finite-Lived Intangible Assets [Line Items]
Goodwill			$ 78,500			$ 78,493