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.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Core Deposit Intangibles - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 01, 2019
Finite-Lived Intangible Assets [Line Items]
Intangible asset amortization	$ 1,486	$ 1,356	$ 4,511	$ 4,404
Maximum
Finite-Lived Intangible Assets [Line Items]
Useful life of core deposit intangibles and other intangibles			10 years
MBT
Finite-Lived Intangible Assets [Line Items]
Core deposit intangible					$ 16,527