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Share-Based Payments (Summary of Shares Available for Issuance) (Details) | Dec. 31, 2017 shares
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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 | 3,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | 2,516,871
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number | 882,490
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 | 1,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | 499,629
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 | 1,817,493
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number | 0

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- Definition [Line Items] for Schedule of Share-Based Compensation Shares Available for Issuance [Table] + References No definition available. + 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://www.xbrl.org/2003/role/presentationRef -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=96867065&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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=96867065&loc=d3e5070-113901 + Details
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- Definition The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=96867065&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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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