Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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- References

No definition available.

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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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Goodwill and Core Deposit Intangibles - Narrative (Details) - USD ($)				3 Months Ended		9 Months Ended
	Apr. 08, 2019	Jul. 01, 2018	Jul. 01, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Impairment of goodwill		$ 0	$ 0
Goodwill [Line Items]
Amortization of intangible assets				$ 3,000,000.0	$ 2,000,000.0	$ 8,300,000	$ 5,500,000
Core Deposits
Goodwill [Line Items]
Amortization of intangible assets				$ 3,000,000.0	$ 2,000,000.0	$ 8,300,000	$ 5,500,000
Weighted average useful lives of related deposits	10 years					10 years