Fair Value of Financial Instruments - Schedule of Fair Value of Financial Instruments (Detail) - USD ($) $ in Millions		Apr. 30, 2016	Oct. 31, 2015
Fair Value, Inputs, Level 1
Financial Instruments
Cash and cash equivalents	[1]	$ 45.7	$ 55.5
Fair Value, Inputs, Level 2
Financial Instruments
Line of credit	[2]	208.9	158.0
Other Noncurrent Assets | Fair Value, Inputs, Level 1
Financial Instruments
Insurance deposits	[3]	11.4	11.4
Other Noncurrent Assets | Fair Value, Inputs, Level 2
Financial Instruments
Interest rate swap	[4]	0.1	0.0
Other Noncurrent Assets | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Financial Instruments
Assets held in funded deferred compensation plan	[5]	4.8	5.3
Other Investments | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Financial Instruments
Investments in auction rate securities	[6]	8.0	13.0
Other Accrued Liabilities | Fair Value, Inputs, Level 2
Financial Instruments
Interest rate swaps	[4]	0.0	0.1
Other Noncurrent Liabilities | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Financial Instruments
Contingent consideration liability	[7]	$ 5.2	$ 5.2

[1] Cash and cash equivalents are stated at nominal value, which equals fair value.

[2] Represents outstanding borrowings under our syndicated line of credit. Due to variable interest rates, the carrying value of outstanding borrowings under our line of credit approximates the fair value. See Note 11, “Line of Credit,” for further information.

[3] Represents restricted insurance deposits that are used to collateralize our insurance obligations and are stated at nominal value, which equals fair value. These insurance deposits are included in “Other noncurrent assets” on the accompanying unaudited consolidated balance sheets. See Note 10, “Insurance,” for further information.

[4] Represents interest rate swap derivatives designated as cash flow hedges. The fair values of the interest rate swaps are estimated based on the present value of the difference between expected cash flows calculated at the contracted interest rates and the expected cash flows at current market interest rates using observable benchmarks for LIBOR forward rates at the end of the period. For 2016 the interest rate swap was included in “Other noncurrent assets,” and for 2015 the interest rate swaps were included in “Other accrued liabilities” on the accompanying unaudited consolidated balance sheets. See Note 11, “Line of Credit,” for more information.

[5] Represents investments held in a Rabbi trust associated with one of our deferred compensation plans, which we include in “Other noncurrent assets” on the accompanying unaudited consolidated balance sheets. The fair value of the assets held in the funded deferred compensation plan is based on quoted market prices.

[6] For investments in auction rate securities, the fair value was based on discounted cash flow valuation models, primarily utilizing unobservable inputs. These amounts are included in “Other investments” on the accompanying unaudited consolidated balance sheets. See Note 9, “Auction Rate Securities,” for further information.

[7] Certain of our acquisitions involve the payment of contingent consideration. Depending on the structure of the contingent consideration arrangement, the fair value of the liability is based on either (i) the expected achievement of certain pre-established revenue goals or (ii) pre-defined forecasted adjusted income from operations using a probability weighted income approach. Our contingent consideration liabilities are included in “Other accrued liabilities” and “Other noncurrent liabilities” on the accompanying unaudited consolidated balance sheets.