Accrued interest percentage.

No definition available.

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- Definition

Ratio of EBITDA as defined in the Credit Agreement to interest expense calculated over a trailing twelve month period.

+ References

No definition available.

+ Details

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- Definition

Debt instrument redemption charges.

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No definition available.

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- Definition

Leverage ratio of total debt to EBITDA.

+ References

No definition available.

+ Details

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- Definition

Maximum leverage ratio.

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No definition available.

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- Definition

Maximum leverage ratio during first four quarter that qualified acquisition is consummated.

+ References

No definition available.

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- Definition

This element represents the maximum ratio of debt less available cash to earnings before interest, taxes, depreciation and amortization (EBITDA) allowed in the reporting entity's credit agreement.

+ References

No definition available.

+ Details

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- Definition

This element represents the minimum ratio of earnings before interest, taxes, depreciation and amortization (EBITDA) to total interest expense required in the reporting entity's credit agreement.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- 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.

+ References

No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

Description of debt redemption features under terms of the debt agreement.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

Date the debt instrument was repurchased, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt premium.

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- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Long-Term Debt and Short-Term Borrowings - Long-Term Debt - Additional Information (Detail) - USD ($)			3 Months Ended		12 Months Ended
	Oct. 31, 2017	Mar. 14, 2013	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Debt Instrument [Line Items]
Proceeds from revolving credit facility			$ 898,000,000	$ 266,000,000
Minimum coverage ratio of EBITDA to total interest expense expressed in percentage			2.00%
Maximum leverage ratio of total debt less available cash to EBITDA expressed in percentage			4.25%
Maximum leverage ratio during first four quarter that qualified acquisition is consummated			4.75%
Coverage ratio of EBITDA to total interest expense expressed in percentage			15.71%
Leverage ratio of total debt less available cash to EBITDA expressed in percentage			91.00%
Write-off of financing costs on extinguished debt			$ 27,982,000
Senior notes					$ 791,700,000
2017 Credit Agreement [Member]
Debt Instrument [Line Items]
Amounts available to borrow under Credit Agreement			$ 2,800,000,000
Revolving credit facility maturity date			Oct. 31, 2022
5.00% Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate of long-term debt					5.00%
Redemption details			In March 2018, we redeemed our 5.00% senior notes in full
Senior notes					$ 791,700,000
5.00% Senior Notes [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate of long-term debt			5.00%		5.00%
Aggregate principal amount issued		$ 800,000,000
Redemption date			Mar. 31, 2018		Mar. 31, 2018
5.00% Senior Notes [Member] \| Senior Notes [Member] \| Redemption on March 15, 2018 [Member]
Debt Instrument [Line Items]
Redemption charges		28,000,000
Senior notes, redemption premium		20,000,000
Write-off of financing costs on extinguished debt		$ 8,000,000
4.875% Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate of long-term debt			4.875%		4.875%
Senior notes			$ 592,200,000		$ 592,000,000
4.875% Senior Notes [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate of long-term debt			4.875%		4.875%
5.25% Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate of long-term debt			5.25%		5.25%
Senior notes			$ 422,500,000		$ 422,400,000
5.25% Senior Notes [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate of long-term debt			5.25%		5.25%
5.00% senior notes due March 15, 2023 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate of long-term debt		5.00%
Debt instrument, maturity date			Mar. 15, 2023
Accrued interest percentage per year		5.00%
Debt Instrument, Frequency of Periodic Payment			semi-annually
Redemption details			The 5.00% senior notes were redeemable at our option, in whole or in part, on March 15, 2018 at a redemption price of 102.5% of the principal amount on that date. We redeemed these notes in full on March 15, 2018 and incurred charges of $28.0 million, including a premium of $20.0 million and the write-off of $8.0 million of unamortized deferred financing costs. We funded this redemption with $550.0 million of borrowings from our tranche A term loan facility and borrowings from our revolving credit facility under our 2017 Credit Agreement.
5.00% senior notes due March 15, 2023 [Member] \| Senior Notes [Member] \| Redemption on March 15, 2018 [Member]
Debt Instrument [Line Items]
Redemption price percentage		102.50%
Revolving credit facility [Member] \| 2017 Credit Agreement [Member]
Debt Instrument [Line Items]
Proceeds from revolving credit facility	$ 83,000,000
Tranche A term loan facility [Member] \| 2017 Credit Agreement [Member]
Debt Instrument [Line Items]
Proceeds from revolving credit facility	$ 200,000,000
Amounts available to borrow under Credit Agreement			$ 750,000,000
Maximum leverage ratio			250.00%
Revolving credit facility maturity date			Oct. 31, 2022
Tranche A term loan facility [Member] \| 5.00% Senior Notes [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued		$ 550,000,000