Fair Value Measurements (Details) - USD ($) $ in Millions | Oct. 31, 2016 | Jul. 31, 2016 |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | $ 550.6 | $ 551.2 |
Long-term investments | 708.4 | 652.8 |
Total assets measured at fair value | 1,259 | 1,204 |
Accrued and other liabilities | 1.2 | 0 |
Total liabilities measured at fair value | 1.2 | 0 |
Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 0 | 0 |
Long-term investments | 0 | 0 |
Total assets measured at fair value | 0 | 0 |
Accrued and other liabilities | 0 | 0 |
Total liabilities measured at fair value | 0 | 0 |
Level 2 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 550.6 | 551.2 |
Long-term investments | 708.4 | 652.8 |
Total assets measured at fair value | 1,259 | 1,204 |
Accrued and other liabilities | 1.2 | 0 |
Total liabilities measured at fair value | 1.2 | 0 |
Level 3 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 0 | 0 |
Long-term investments | 0 | 0 |
Total assets measured at fair value | 0 | 0 |
Accrued and other liabilities | 0 | 0 |
Total liabilities measured at fair value | 0 | 0 |
Commercial paper | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 17.9 | 3 |
Commercial paper | Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 0 | 0 |
Commercial paper | Level 2 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 17.9 | 3 |
Commercial paper | Level 3 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 0 | 0 |
Corporate debt securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 110.3 | 121.4 |
Long-term investments | 188.7 | 166.1 |
Corporate debt securities | Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 0 | 0 |
Long-term investments | 0 | 0 |
Corporate debt securities | Level 2 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 110.3 | 121.4 |
Long-term investments | 188.7 | 166.1 |
Corporate debt securities | Level 3 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 0 | 0 |
Long-term investments | 0 | 0 |
U.S. government and agency securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 422.4 | 426.8 |
Long-term investments | 514.3 | 481.3 |
U.S. government and agency securities | Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 0 | 0 |
Long-term investments | 0 | 0 |
U.S. government and agency securities | Level 2 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 422.4 | 426.8 |
Long-term investments | 514.3 | 481.3 |
U.S. government and agency securities | Level 3 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Short-term investments | 0 | 0 |
Long-term investments | 0 | 0 |
Certificates of deposit | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Long-term investments | 5.4 | 5.4 |
Certificates of deposit | Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Long-term investments | 0 | 0 |
Certificates of deposit | Level 2 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Long-term investments | 5.4 | 5.4 |
Certificates of deposit | Level 3 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Long-term investments | 0 | 0 |
Foreign currency forward contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Accrued and other liabilities | 1.2 | 0 |
Foreign currency forward contracts | Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Accrued and other liabilities | 0 | 0 |
Foreign currency forward contracts | Level 2 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Accrued and other liabilities | 1.2 | 0 |
Foreign currency forward contracts | Level 3 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis | | |
Accrued and other liabilities | $ 0 | $ 0 |