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Stock-Based Compensation (Details) - Equity and Incentive Plan, 2017 [Member] shares in Millions | 3 Months Ended | 6 Months Ended
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Jun. 30, 2017 shares | Jun. 30, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Maximum number of shares authorized | 5.5 | 5.5
Measurement period, performance-based restricted stock units | 1 year |
Number of restricted stock units granted |  | 0.6
Time-based Restricted Stock Units [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Vesting period | 4 years |
Performance-based Restricted Stock Units Graded Vesting [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Vesting period | 4 years |
Performance-based Restricted Stock Units Cliff Vesting [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Vesting period | 3 years |
Measurement period for additional performance metrics | 3 years |

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- Definition Measurement period for additional performance metrics as defined in the award agreement of certain restricted stock unit awards. + References No definition available. + Details
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- Definition Measurement period for a performance metric as defined in the restricted stock unit awards agreement. + References No definition available. + Details
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- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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)(1) -URI http://asc.fasb.org/extlink&oid=6415400&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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- 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=6415400&loc=d3e5070-113901 + Details
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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + Details
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