Business combination acquisition related costs after tax.

No definition available.

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- Definition

Number of bank branches acquired.

+ References

No definition available.

+ Details

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- Definition

Number of branches.

+ References

No definition available.

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- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

+ References

No definition available.

+ Details

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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

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
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-Subparagraph (h)(2)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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-Subparagraph (h)(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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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
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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Business Combinations - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) Branch	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Feb. 08, 2019 USD ($) Branch	Aug. 23, 2018 Branch	May 04, 2018 USD ($)
Business Acquisition [Line Items]
Goodwill	$ 136,432	$ 131,712	$ 104,907
MidFirst Bank [Member]
Business Acquisition [Line Items]
Acquisition-related costs	902
Acquisition-related costs after tax	684
Goodwill	$ 4,720			$ 4,720
Number of branches acquired \| Branch	3
Total combined revenue	$ 200,807	183,022
Net income	25,216	33,856
MidFirst Bank [Member] \| Guymon, Oklahoma [Member]
Business Acquisition [Line Items]
Number of branches \| Branch				2
MidFirst Bank [Member] \| Cordell, Oklahoma [Member]
Business Acquisition [Line Items]
Number of branches \| Branch				1
City Bank and Trust Company [Member]
Business Acquisition [Line Items]
Number of branches \| Branch					1
Acquisition-related costs		1,387
Acquisition-related costs after tax		1,054
Goodwill	$ 5,824			$ 5,824
Number of branches acquired \| Branch	1
Kansas Bank Corporation [Member]
Business Acquisition [Line Items]
Acquisition-related costs		4,360	14
Acquisition-related costs after tax		3,349	9
Goodwill	$ 14,010					$ 14,010
Number of branches acquired \| Branch	5
Voting interest acquired						100.00%
Adams Dairy Bancshares, Inc. [Member]
Business Acquisition [Line Items]
Acquisition-related costs		1,217	4
Acquisition-related costs after tax		961	2
Goodwill	$ 8,465					$ 8,465
Number of branches acquired \| Branch	1
Voting interest acquired						100.00%
City Bank, KBC and Adams mergers [Member]
Business Acquisition [Line Items]
Total combined revenue		203,860	147,222
Net income		$ 49,801	$ 27,108