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Share-based Compensation Plans: Performance Plan Share Units (Details) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance Share Award Payout, Shares of Common Stock Percentage | 100.00% |  |
Performance Shares |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance Share Award Payout, Shares of Common Stock Percentage | 50.00% |  |
Performance Share Award, Percentage of Target | 40.17% |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period | 3 years |  |
Award vesting period | 3 years |  |
Performance Shares | Minimum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance Share Award, Percentage of Target | 0.00% | 0.00% | 0.00%
Performance Shares | Maximum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance Share Award, Percentage of Target | 200.00% | 200.00% | 200.00%

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- Definition The percentage target for payout of equity compensation awards + References No definition available. + Details
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- Definition Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition 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. + References No definition available. + Details
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