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Stock-Based Compensation (Details) - 2013 Plan - shares | Jun. 30, 2015 | Apr. 30, 2013
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Stock-based compensation |  |
Maximum number of shares available under the Plan |  | 6,500,000
Stock Options |  |
Stock-based compensation |  |
Number of shares counted by each award | 1 |
Stock Appreciation Rights |  |
Stock-based compensation |  |
Number of shares counted by each award | 1 |
Stock-settled award other than an option, stock appreciation right or award for which the recipient pays intrinsic value |  |
Stock-based compensation |  |
Number of shares counted by each award | 1.75 |

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- Definition Represents the number of shares counted by each award against the aggregate share limit. + References No definition available. + 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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