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Share-Based Payments (Summary of Shares Available for Issuance) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Dividend Equivalent Units [Member] |  |  |
Schedule of Share-Based Compensation Shares Available for Issuance [Line Items] |  |  |
Total intrinsic value of shares vested | $ 0.6 | $ 0.7 | $ 0.8
Omnibus Stock Plan 2014 [Member] |  |  |
Schedule of Share-Based Compensation Shares Available for Issuance [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 4,750,000 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | 2,713,667 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number | 660,697 |  |
Employee Stock [Member] |  |  |
Schedule of Share-Based Compensation Shares Available for Issuance [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 5,500,000 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | 1,184,849 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number | 0 |  |
Agent Stock Purchase Plan [Member] |  |  |
Schedule of Share-Based Compensation Shares Available for Issuance [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 3,000,000 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | 1,608,234 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number | 0 |  |

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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 Number of equity instruments other than options outstanding, including both vested and non-vested instruments. + 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)(1)(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Number of shares authorized for issuance 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 (a)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + 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 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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