- Fair Value Measurements (Details) - USD ($) $ in Thousands	Jan. 31, 2020	Oct. 31, 2019
Assets:
Debt securities	$ 120,143
Liabilities:
Contingent consideration	3,700
Fair value, Measurements, Recurring
Assets:
Money market funds	632,620	$ 759,114
Total assets measured at fair value	803,216	880,638
Liabilities:
Contingent consideration	3,705	3,705
Total liabilities measured at fair value	26,640	24,833
Fair value, Measurements, Recurring \| Level 1
Assets:
Money market funds	632,620	759,114
Total assets measured at fair value	682,800	759,114
Liabilities:
Contingent consideration	0	0
Total liabilities measured at fair value	0	0
Fair value, Measurements, Recurring \| Level 2
Assets:
Money market funds	0	0
Total assets measured at fair value	120,416	121,524
Liabilities:
Contingent consideration	0	0
Total liabilities measured at fair value	22,935	21,128
Fair value, Measurements, Recurring \| Level 3
Assets:
Money market funds	0	0
Total assets measured at fair value	0	0
Liabilities:
Contingent consideration	3,705	3,705
Total liabilities measured at fair value	3,705	3,705
Foreign Currency Forward Contracts \| Fair value, Measurements, Recurring
Assets:
Derivative asset	273	1,570
Liabilities:
Derivative liability	710	35
Foreign Currency Forward Contracts \| Fair value, Measurements, Recurring \| Level 1
Assets:
Derivative asset	0	0
Liabilities:
Derivative liability	0	0
Foreign Currency Forward Contracts \| Fair value, Measurements, Recurring \| Level 2
Assets:
Derivative asset	273	1,570
Liabilities:
Derivative liability	710	35
Foreign Currency Forward Contracts \| Fair value, Measurements, Recurring \| Level 3
Assets:
Derivative asset	0	0
Liabilities:
Derivative liability	0	0
Forward Starting Interest Rate Swaps
Liabilities:
Derivative liability		21,093
Forward Starting Interest Rate Swaps \| Fair value, Measurements, Recurring
Liabilities:
Derivative liability	22,225
Forward Starting Interest Rate Swaps \| Fair value, Measurements, Recurring \| Level 1
Liabilities:
Derivative liability	0	0
Forward Starting Interest Rate Swaps \| Fair value, Measurements, Recurring \| Level 2
Liabilities:
Derivative liability	22,225	21,093
Forward Starting Interest Rate Swaps \| Fair value, Measurements, Recurring \| Level 3
Liabilities:
Derivative liability	0	0
Bond mutual fund \| Fair value, Measurements, Recurring
Assets:
Debt securities	50,180
Bond mutual fund \| Fair value, Measurements, Recurring \| Level 1
Assets:
Debt securities	50,180
Bond mutual fund \| Fair value, Measurements, Recurring \| Level 2
Assets:
Debt securities	0
Bond mutual fund \| Fair value, Measurements, Recurring \| Level 3
Assets:
Debt securities	0
U.S. government obligations \| Fair value, Measurements, Recurring
Assets:
Debt securities	120,143	119,954
U.S. government obligations \| Fair value, Measurements, Recurring \| Level 1
Assets:
Debt securities	0	0
U.S. government obligations \| Fair value, Measurements, Recurring \| Level 2
Assets:
Debt securities	120,143	119,954
U.S. government obligations \| Fair value, Measurements, Recurring \| Level 3
Assets:
Debt securities	$ 0	$ 0

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