Number of branches closed.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
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-Subparagraph (e)
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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.

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Premises and Equipment - Additional Information (Details)	3 Months Ended	12 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2020 USD ($) branch	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Property Plant And Equipment [Line Items]
Depreciation and amortization (including capital lease amortization) included in noninterest expense		$ 20,200,000	$ 17,300,000	$ 14,400,000
Number of branches closed \| branch		12
Premises
Property Plant And Equipment [Line Items]
Impairment charge	$ 1,600,000		0	0
Equipment
Property Plant And Equipment [Line Items]
Impairment charge	$ 1,600,000		$ 0	$ 0