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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Other Intangibles - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Sep. 01, 2019
Business Acquisition [Line Items]
Intangible asset amortization	$ 5,994	$ 6,719	$ 5,647
Minimum
Business Acquisition [Line Items]
Useful life of core deposit intangibles and other intangibles	2 years
Maximum
Business Acquisition [Line Items]
Useful life of core deposit intangibles and other intangibles	10 years
MBT
Business Acquisition [Line Items]
Core deposit intangible				$ 16,527