Additional line of credit facility borrowing capacity.

No definition available.

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- Definition

Debt Instrument Maturity Year.

+ References

No definition available.

+ Details

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- Definition

Interest rate under multicurrency facility.

+ References

No definition available.

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- Definition

Line of credit facility covenant compliance debt to capitalization percentage.

+ References

No definition available.

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- Definition

Line of credit facility covenant terms maximum debt to capitalization percentage.

+ References

No definition available.

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- Definition

Line of credit facility covenant terms maximum debt to equity percentage.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility extended borrowing capacity.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Outstanding letters of credit under various bilateral committed letter of credit facilities.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Write off Of unamortized discount and debt issuance cost.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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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.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt premium.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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-Section 55
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of accrued but unpaid interest on deposit liabilities.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
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-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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Balance Type:	credit
Period Type:	instant

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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Period Type:	duration

- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- 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.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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- Definition

Amount of long-term debt classified as other.

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Period Type:	instant

- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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- Definition

The excess of the (1) fair value of consideration transferred to the holders of a security in excess of (2) the carrying amount of the security reported on the registrant's balance sheet, which will be deducted from net earnings to derive net earnings available to common shareholders. This amount is generally an adjustment considered in the computation of earnings per share.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt.

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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.

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Debt - Additional Information (Detail) - USD ($)		3 Months Ended
Debt - Additional Information (Detail) - USD ($)	Apr. 09, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Interest rate under multi currency facility			LIBOR, NIBOR or CDOR plus 1.125%
Capitalization ratio, Maximum			60.00%
Capitalization ratio, Actual			29.00%
Funds available under revolving credit facility			$ 2,000,000,000.0
Other debt			87,000,000	$ 70,000,000
Outstanding letters of credit under various bilateral letter of credit facilities			444,000,000
Carrying value of Unsecured Senior Notes			1,764,000,000	1,764,000,000
Unsecured Debt [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Instrument [Line Items]
Fair value of Unsecured Senior Notes			1,690,000,000	$ 1,833,000,000
2.60% Unsecured Senior Notes Due December 2022 [Member] \| Scenario Forecast [Member]
Debt Instrument [Line Items]
Loss on extinguishment of debt		$ (7,100,000)
Premium		6,800,000
Write off Of unamortized discount and debt issuance cost		$ 300,000
2.60% Unsecured Senior Notes Due December 2022 [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Repayment of unsecured note outstanding balance	$ 182,000,000
Senior notes interest rate	2.60%
Redemption of unsecured note	$ 191,000,000
Redemption premium	6,800,000
Accrued and unpaid interest	$ 1,700,000
Debt Instrument Maturity Date	2029
Noncontrolling Interests [Member]
Debt Instrument [Line Items]
Other debt			$ 25,000,000
Canadian Dollar Offered Rate (CDOR) [Member]
Debt Instrument [Line Items]
Variable rate			1.125%
Five Year Unsecured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility, borrowing capacity			$ 2,000,000,000.0
Credit facility, maturity date			Oct. 30, 2024
Credit facility, extendable borrowing capacity			$ 3,000,000,000.0
Variable rate basis			LIBOR, NIBOR or CDOR plus
Outstanding letters of credit issued			$ 0
Unsecured Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility, Period			5 years
Foreign Line of Credit [Member]
Debt Instrument [Line Items]
Variable rate			1.40%
Additional line of credit facility borrowing capacity			$ 150,000,000
Debt to equity ratio maximum			75.00%