Employee Benefit Plans - Supplemental Employee Retirement Plan Assets (Details) - Supplemental Employee Retirement Plan - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Cost
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plan assets	$ 5.8	$ 6.0
Market
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plan assets	7.2	7.3
Money market fund | Cost
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plan assets	0.1	0.0
Money market fund | Market
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plan assets	0.1	0.0
Company stock | Cost
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plan assets	1.2	1.5
Company stock | Market
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plan assets	2.2	2.3
Equity Securities | Cost
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plan assets	4.5	4.5
Equity Securities | Market
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plan assets	$ 4.9	$ 5.0