Goodwill and purchased intangible assets Purchased intangible assets (Details) - USD ($) $ in Thousands |
Apr. 30, 2016 |
Oct. 31, 2015 |
|---|---|---|
| Goodwill [Line Items] | ||
| Gross Carrying Amount | $ 768,023 | $ 707,073 |
| Accumulated Amortization | (400,006) | (389,556) |
| Total | 368,017 | 317,517 |
| Net Carrying Amount | 368,017 | |
| Customer Relationships [Member] | ||
| Goodwill [Line Items] | ||
| Gross Carrying Amount | 662,417 | 591,930 |
| Accumulated Amortization | (333,778) | (298,812) |
| Net Carrying Amount | 328,639 | 293,118 |
| Other Intangible Assets [Member] | ||
| Goodwill [Line Items] | ||
| Gross Carrying Amount | 105,606 | 115,143 |
| Accumulated Amortization | (66,228) | (90,744) |
| Net Carrying Amount | $ 39,378 | $ 24,399 |