Employee Benefits and Stock-Based Compensation - Annual Discretionary Bonus Grant (Details) shares in Millions	12 Months Ended
Dec. 31, 2014 shares
Restricted Stock Unit Bonus Grant
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Granted or Expected to Be Granted in Next Fiscal Period	1.4

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.

No definition available.

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