Quarterly Financial Data (Unaudited) - Additional Disclosures (Details) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
May. 31, 2015 |
Feb. 28, 2015 |
Nov. 30, 2014 |
Aug. 31, 2014 |
May. 31, 2014 |
Feb. 28, 2014 |
Nov. 30, 2013 |
Aug. 31, 2013 |
May. 31, 2015 |
May. 31, 2014 |
May. 31, 2013 |
|
| Error Corrections and Prior Period Adjustments Restatement [Line Items] | |||||||||||
| Service revenue | $ 681.4 | $ 693.6 | $ 665.9 | $ 656.6 | $ 628.8 | $ 639.9 | $ 606.4 | $ 603.1 | $ 2,697.5 | $ 2,478.2 | $ 2,285.2 |
| Total revenue | $ 692.2 | 704.3 | 676.3 | 666.8 | $ 639.0 | $ 650.4 | $ 616.4 | $ 613.1 | $ 2,739.6 | $ 2,518.9 | $ 2,326.2 |
| Scenario, Previously Reported [Member] | |||||||||||
| Error Corrections and Prior Period Adjustments Restatement [Line Items] | |||||||||||
| Service revenue | 626.0 | 600.5 | 597.9 | ||||||||
| Total revenue | $ 636.5 | $ 610.5 | $ 607.9 | ||||||||
| X | ||||||||||
- 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. No definition available.
|
| X | ||||||||||
- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Aggregate revenue during the period from services rendered in the normal course of business, after deducting allowances and discounts. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Details
|