The amount of deposit recognized as of the acquisition date.

No definition available.

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- Definition

Number of bank branches.

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No definition available.

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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

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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.

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No definition available.

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- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the gross contractual amounts receivable, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Amount of assets acquired at the acquisition date.

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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.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Acquisitions - Textual (Details) $ in Thousands			12 Months Ended
Acquisitions - Textual (Details) $ in Thousands	Oct. 19, 2017 USD ($) financial_center branch shares	May 15, 2017 USD ($) branch shares	Dec. 31, 2017 USD ($)	Sep. 30, 2018 USD ($)	Oct. 18, 2017 USD ($)	Jun. 30, 2017 USD ($)	May 14, 2017 USD ($)
Business Acquisition [Line Items]
Goodwill			$ 842,651	$ 845,687
OKSB Merger
Business Acquisition [Line Items]
Shares issued (in shares) \| shares	14,488,604
Shares issued	$ 431,400
Payments to acquire businesses, gross	$ 94,900
Number of bank branches \| branch	29
Total assets acquired	$ 2,690,915				$ 2,686,489
Gross value of loans acquired	1,996,453		2,021,000		2,039,524
Total deposits acquired	1,966,355				1,968,568
Goodwill	$ 229,144				13,545
Revenue attributable to acquisition			29,200
Net income attributable to acquisition			10,500
First Texas Merger
Business Acquisition [Line Items]
Shares issued (in shares) \| shares	12,999,840
Shares issued	$ 387,100
Payments to acquire businesses, gross	$ 70,000
Number of bank branches \| financial_center	15
Total assets acquired	$ 2,427,226				2,453,283
Gross value of loans acquired	2,208,378		2,246,000		2,246,212
Total deposits acquired	1,881,658				1,881,941
Goodwill	$ 240,843				$ 37,227
Revenue attributable to acquisition			27,600
Net income attributable to acquisition			5,700
OKSB and First Texas Acquisitions
Business Acquisition [Line Items]
Acquisition related costs			$ 9,400
Hardeman County Investment Company, Inc.
Business Acquisition [Line Items]
Shares issued (in shares) \| shares		1,599,940
Shares issued		$ 42,600
Payments to acquire businesses, gross		$ 30,000
Number of bank branches \| branch		10
Total assets acquired		$ 462,924					$ 468,829
Gross value of loans acquired		251,649				$ 254,200	257,641
Total deposits acquired		388,976					389,344
Goodwill		$ 29,371					$ 11,485