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

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Balance Type:	credit
Period Type:	instant

- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

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- Definition

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

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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- Definition

Including the current and noncurrent portions, 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). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

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Senior Notes (Detail) - USD ($)	Dec. 06, 2019	May 08, 2018	Dec. 31, 2020	Sep. 30, 2020
Debt Instrument [Line Items]
Carrying value of Senior Notes			$ 750,000,000	$ 750,000,000
Fair value of Senior Notes			816,000,000	800,750,000
Debt issuance costs			10,200,000	10,600,000
May 2018 Senior Notes
Debt Instrument [Line Items]
Senior Notes issued in a private placement to a group of institutional investors		$ 400,000,000
Carrying value of Senior Notes			400,000,000	400,000,000
Fair value of Senior Notes			452,000,000	442,000,000
Debt instrument, maturity date		May 15, 2026
Debt Instrument, Interest Rate, Stated Percentage		5.25%
Dec 2019 Senior Notes
Debt Instrument [Line Items]
Senior Notes issued in a private placement to a group of institutional investors	$ 350,000,000
Carrying value of Senior Notes			350,000,000	350,000,000
Fair value of Senior Notes			$ 364,000,000	$ 358,750,000
Debt instrument, maturity date	Jun. 15, 2028
Debt Instrument, Interest Rate, Stated Percentage	4.00%