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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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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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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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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Goodwill and intangible assets - Narrative (Details) - USD ($)	3 Months Ended		12 Months Ended
	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment			$ 0	$ 0
Farmers National \| Core deposit intangible
Finite-Lived Intangible Assets [Line Items]
Intangible assets acquired		$ 2,490,000
Weighted average life of intangible assets acquired		4 years
Franklin Financial Network, Inc. \| Core deposit and other intangibles
Finite-Lived Intangible Assets [Line Items]
Intangible assets acquired	$ 7,670,000
Weighted average life of intangible assets acquired	4 years