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Nonqualified Benefit Plans Contributions (Details 14) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Unfunded Plan | Nonqualified Plan      
Defined Benefit Plan Disclosure [Line Items]      
Nonqualified Defined Contribution Plan, Cost $ 2.4 $ 1.8 $ 1.6