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Equity (Stock-Based Compensation Plans - Narrative) (Details) - shares | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
2015 Stock Plan |  |  |  |
Equity - Stock-based Compensation Plans [Line Items] |  |  |  |
Aggregate number of shares authorized for issuance |  | 31,886,521 |  |
Other Stock And Incentive Plans |  |  |  |
Equity - Stock-based Compensation Plans [Line Items] |  |  |  |
Deferred shares |  | 686,770 |  |
2015 Director Stock Plan |  |  |  |
Equity - Stock-based Compensation Plans [Line Items] |  |  |  |
Aggregate number of shares authorized for issuance |  | 1,469,329 |  |
Other Director Stock Plans |  |  |  |
Equity - Stock-based Compensation Plans [Line Items] |  |  |  |
Deferred shares |  | 323,898 |  |
Stock Options |  |  |  |
Equity - Stock-based Compensation Plans [Line Items] |  |  |  |
Award Expiration Date |  | 10 years | 10 years | 10 years
Stock Options | Maximum |  |  |  |
Equity - Stock-based Compensation Plans [Line Items] |  |  |  |
Vesting period |  | 3 years |  |
Stock Options | Liability Awards Plan |  |  |  |
Equity - Stock-based Compensation Plans [Line Items] |  |  |  |
Paid |  | 0 |  |
Performance Shares |  |  |  |
Equity - Stock-based Compensation Plans [Line Items] |  |  |  |
Paid |  | (1,489,328) |  |
Performance Factor |  |  | 141.30% |
Performance Shares | Scenario, Forecast |  |  |  |
Equity - Stock-based Compensation Plans [Line Items] |  |  |  |
Paid | (1,174,602) |  |  |
Performance Shares | Minimum |  |  |  |
Equity - Stock-based Compensation Plans [Line Items] |  |  |  |
Future Performance Factor |  | 0.00% |  |
Performance Shares | Maximum |  |  |  |
Equity - Stock-based Compensation Plans [Line Items] |  |  |  |
Future Performance Factor |  | 175.00% |  |
Performance Shares | Liability Awards Plan |  |  |  |
Equity - Stock-based Compensation Plans [Line Items] |  |  |  |
Paid |  | (156,900) |  |
Performance Shares | Liability Awards Plan | Scenario, Forecast |  |  |  |
Equity - Stock-based Compensation Plans [Line Items] |  |  |  |
Paid | (154,904) |  |  |

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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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