Number of branches closed permanently.

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Write off impairment charge, right-of-use assets.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation.

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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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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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Indicates (true false) whether lessee has option to extend operating lease.

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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

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The amount of revenue recognized for the period under subleasing arrangements.

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Leases - Additional Information (Details) $ in Millions		12 Months Ended
Leases - Additional Information (Details) $ in Millions	Jan. 22, 2021 USD ($) branch	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Lessee Lease Description [Line Items]
Operating lease, existence of option to extend		true
Operating lease, option to extend		through 2052
Sublease, existence of option to extend		true
Sublease, option to extend		through 2033
Rent expense				$ 19.3
Sublease income				7.6
Rental income from operating leases, including subleases		$ 10.3	$ 10.7	$ 8.7
Board of Directors \| Subsequent Event
Lessee Lease Description [Line Items]
Total charge related to branch closure	$ 5.6
Number of branches closed \| branch	12
Write off impairment charge, right-of-use assets	$ 2.5