Cash equivalent maturity description

No definition available.

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- Definition

Line of credit facility collateral amount.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Line Of Credit Facility Expiration Month Year

+ References

No definition available.

+ Details

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- Definition

Short Term Debt Textual [Abstract]

+ References

No definition available.

+ Details

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- 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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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Period Type:	instant

- Definition

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

+ References

+ Details

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- Definition

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

+ References

+ Details

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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.

+ References

+ Details

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- Definition

The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Details

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- Details

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- Details

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- Details

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- Details

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Short-Term Debt - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended		12 Months Ended
	Dec. 31, 2018	Apr. 30, 2015	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2018	Dec. 31, 2015	Dec. 31, 2014
Short Term Debt (Textual) [Abstract]
Cash equivalent maturity description			Less than one year
Maximum borrowing capacity of short term debt	$ 350		$ 350
Short-term debt	407		407	$ 0
Line of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Short Term Debt (Textual) [Abstract]
Maximum borrowing capacity of short term debt		$ 750
Outstanding amounts	0		$ 0	0
Line of credit facility, expiry date			Apr. 02, 2020
Credit facility, spread on variable rate		0.785%
Interest rate basis on outstanding principal balances of the line of credit			A U.S. LIBOR rate
Nationwide Financial Services [Member]
Short Term Debt (Textual) [Abstract]
Maximum borrowing capacity of short term debt	$ 45		$ 45
Credit facility, spread on variable rate	3.55%
Line of credit facility, expiry period	2019-03
Federal Home Loan Bank Borrowings [Member]
Short Term Debt (Textual) [Abstract]
Maximum borrowing capacity of short term debt					$ 250
Eligible collateral for short term borrowings			5,800	6,500
Outstanding amounts	$ 0		$ 0	0
Line of credit facility, expiry date			Mar. 22, 2019
Amounts outstanding under agreement with Federal Home Loan Bank	$ 0		$ 0	$ 0
$600 million Commercial Paper Program [Member]
Short Term Debt (Textual) [Abstract]
Maximum borrowing capacity of short term debt							$ 600
$750 million Commercial Paper Program [Member]
Short Term Debt (Textual) [Abstract]
Maximum borrowing capacity of short term debt						$ 750
Custodial Bank [Member]
Short Term Debt (Textual) [Abstract]
Interest rate basis on outstanding principal balances of the line of credit			One-month U.S. LIBOR.