Subsequent Event - Additional Information (Detail) - Pegasus Bank [Member] - USD ($) $ in Millions	Apr. 23, 2019	Dec. 31, 2018
Subsequent Event [Line Items]
Total assets acquired		$ 639.1
Loans		367.4
Deposits		$ 595.3
Subsequent Event [Member]
Subsequent Event [Line Items]
Business acquisition, date of agreement	Apr. 23, 2019
Contract price	$ 122.0

Business acquisition purchase price allocation deposits assumed.

No definition available.

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- Definition

Business acquisition purchase price allocation loans acquired.

+ References

No definition available.

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- Definition

Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
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- Definition

Amount of assets acquired at the acquisition date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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