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Retirement Plans and Postretirement Benefit Plans - Defined Benefit Plan, Plan Assets, Category (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
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U.S. common stocks [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | $ 56.9 | $ 71.9 |
U.S. treasury notes and bonds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets | [1] | 42.4 | 44.6 |
Mortgage-backed securities |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 22.0 | 26.2 |
Corporate fixed income and other securities [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 54.6 | 65.5 |
Commingled fund [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets | [2] | 13.8 | 18.2 |
Foreign government bonds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.2 | 0.5 |
Municipal Bonds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.3 | 0.9 |
Money Market Funds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 1.3 | 5.9 |
Interest and dividends receivable [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 1.4 | 1.6 |
Payable to broker for securities purchased [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | (14.2) | (25.2) |
Mutual Funds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 55.3 | 60.4 |
Preferred Stock [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 1.0 | 1.5 |
Cash Collateral [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.3 | 0.3 |
Receivable (foreign currency) [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.1 | 0.1 |
Receivable from broker for securities sold [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 8.3 | 20.6 |
Total Plan investments [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 248.2 | 296.0 |
Plan Assets Attributable to Affiliates |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | (52.3) | (54.1) |
Total Plan assets [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 243.7 | 293.0 |
Total Plan assets [Member] | Og and E [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 191.4 | 238.9 |
Fair Value, Inputs, Level 1 [Member] | U.S. common stocks [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 56.9 | 71.9 |
Fair Value, Inputs, Level 1 [Member] | U.S. treasury notes and bonds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets | [1] | 42.4 | 44.6 |
Fair Value, Inputs, Level 1 [Member] | Mortgage-backed securities |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 |
Fair Value, Inputs, Level 1 [Member] | Corporate fixed income and other securities [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 |
Fair Value, Inputs, Level 1 [Member] | Commingled fund [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets | [2] | 0.0 | 0.0 |
Fair Value, Inputs, Level 1 [Member] | Foreign government bonds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 |
Fair Value, Inputs, Level 1 [Member] | Municipal Bonds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 |
Fair Value, Inputs, Level 1 [Member] | Money Market Funds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 |
Fair Value, Inputs, Level 1 [Member] | Mutual Funds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 55.3 | 60.4 |
Fair Value, Inputs, Level 1 [Member] | Preferred Stock [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 1.0 | 1.5 |
Fair Value, Inputs, Level 1 [Member] | Cash Collateral [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.3 | 0.3 |
Fair Value, Inputs, Level 1 [Member] | Receivable (foreign currency) [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 |
Fair Value, Inputs, Level 1 [Member] | Total Plan investments [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 155.9 | 178.7 |
Fair Value, Inputs, Level 2 [Member] | U.S. common stocks [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 |
Fair Value, Inputs, Level 2 [Member] | U.S. treasury notes and bonds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets | [1] | 0.0 | 0.0 |
Fair Value, Inputs, Level 2 [Member] | Mortgage-backed securities |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 22.0 | 26.2 |
Fair Value, Inputs, Level 2 [Member] | Corporate fixed income and other securities [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 54.6 | 65.5 |
Fair Value, Inputs, Level 2 [Member] | Commingled fund [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets | [2] | 0.0 | 0.0 |
Fair Value, Inputs, Level 2 [Member] | Foreign government bonds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.2 | 0.5 |
Fair Value, Inputs, Level 2 [Member] | Municipal Bonds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.3 | 0.9 |
Fair Value, Inputs, Level 2 [Member] | Money Market Funds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 |
Fair Value, Inputs, Level 2 [Member] | Mutual Funds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 |
Fair Value, Inputs, Level 2 [Member] | Preferred Stock [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 |
Fair Value, Inputs, Level 2 [Member] | Cash Collateral [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 |
Fair Value, Inputs, Level 2 [Member] | Receivable (foreign currency) [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.1 | 0.1 |
Fair Value, Inputs, Level 2 [Member] | Total Plan investments [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 77.2 | 93.2 |
Net Asset Value [Member] | U.S. common stocks [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 | [3]
Net Asset Value [Member] | U.S. treasury notes and bonds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets | [1] | 0.0 | 0.0 | [3]
Net Asset Value [Member] | Mortgage-backed securities |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 | [3]
Net Asset Value [Member] | Corporate fixed income and other securities [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 | [3]
Net Asset Value [Member] | Commingled fund [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets | [2] | 13.8 | 18.2 | [3]
Net Asset Value [Member] | Foreign government bonds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 | [3]
Net Asset Value [Member] | Municipal Bonds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 | [3]
Net Asset Value [Member] | Money Market Funds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 1.3 | 5.9 | [3]
Net Asset Value [Member] | Mutual Funds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 | [3]
Net Asset Value [Member] | Preferred Stock [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 | [3]
Net Asset Value [Member] | Cash Collateral [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 | [3]
Net Asset Value [Member] | Receivable (foreign currency) [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | 0.0 | 0.0 | [3]
Net Asset Value [Member] | Total Plan investments [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair Value of Plan Assets |  | $ 15.1 | $ 24.1 | [3]
[1] | This category represents U.S. Treasury notes and bonds with a Moody's Investors Service rating of Aaa and Government Agency Bonds with a Moody's Investors Service rating of A1 or higher.
[2] | This category represents units of participation in a commingled fund that primarily invested in stocks of international companies and emerging markets.
[3] | GAAP allows the measurement of certain investments that do not have a readily determinable fair value at the net asset value. These investments do not consider the observability of inputs; therefore, they are not included within the fair value hierarchy.

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