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Share Based Compensation Plans: Performance Share Plan (Details) $ / shares in Units, shares in Thousands, $ in Thousands | 12 Months Ended
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Dec. 31, 2021 USD ($) $ / shares shares | Dec. 31, 2020 USD ($) $ / shares shares | Dec. 31, 2019 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance Share Award Payout, Shares of Common Stock Percentage | 100.00% |  |
Unrecognized compensation expense | $ | $ 14,000 |  |
Stock Issued During Period, Shares, Treasury Stock Reissued | 28 | 14 | 44
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Share-based Liabilities Paid | $ | $ 1,647 | $ 1,100 | $ 2,860
Restricted Stock and RSUs, total fair value of shares vested | $ | $ 3,294 | $ 2,199 | $ 5,720
Performance Goal - Percentile of Peer Group Performance | 3000.00% |  |
Performance Shares |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance Share Award Payout, Cash Percentage | 50.00% |  |
Performance Share Award Payout, Shares of Common Stock Percentage | 50.00% |  |
The percentage paid in cash for the accrued equity portion of the performance share plan upon change in control | 100.00% |  |
Unrecognized compensation expense | $ | $ 2,100 |  |
Performance Shares, Number of Shares Authorized |  | 36 | 36
Performance Share Award, Percentage of Target | 40.17% |  |
Weighted Average Grant Date Fair Value (usd per share) | $ / shares |  | $ 81.42 | $ 68.72
Blended volatility |  | 18.00% | 21.00%
Volatility Rate - Historic | 0.50 |  |
Volatility Rate - Implied | 0.50 |  |
Volatility range for the peer group, Maximum | 76.00% |  |
Target shares, value | $ | $ 1,000 |  |
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%
Performance Shares, Equity Awards |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance Shares, Number of Shares Authorized | 36 | 61 |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value | $ / shares | $ 68.14 | $ 69.71 |
Performance Shares, Granted in Period | 0 |  |
Weighted Average Grant Date Fair Value (usd per share) | $ / shares | $ 0 |  |
Shares Forfeited | 0 |  |
Forfeited (usd per share) | $ / shares | $ 0 |  |
Shares Vested | (25) |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value | $ / shares | $ 61.82 |  |
Performance Shares, Liability Awards |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance Shares, Number of Shares Authorized | 36 | 61 |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value | $ / shares | $ 31.51 |  |
Performance Shares, Granted in Period | 0 |  |
Shares Forfeited | 0 |  |
Shares Vested | (25) |  |

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- Definition Share-based Compensation Arrangement by Share Based Payment Award, Performance Goal - The Company's Total Shareholder Return for the Prescribed Period as a Percentile of Peer Group Performance + References No definition available. + Details
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- Definition Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event. + 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 (c)(2)(iii)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options. + 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 (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Amount of cash paid to settle liability for award under share-based payment arrangement. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. + 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 (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement. + 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 (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References No definition available. + Details
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