Percent Of Construction Costs Capitalized

No definition available.

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- Definition

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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- Definition

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

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

- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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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

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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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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-Publisher FASB
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-Paragraph 1
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Amount of cash inflow from issuance of long-term debt classified as other.

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-Publisher FASB
-Name Accounting Standards Codification
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Debt and Financing Arrangements Long-Term Debt Instruments (Details) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended
	Oct. 31, 2018	Sep. 30, 2018	Aug. 01, 2018	Mar. 15, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-Term Debt		$ 3,204,044			$ 2,191,576
Long-term debt due within one year		1,681			$ 251,430
6.05% due 2018
Debt Instrument [Line Items]
Retirement of debt		$ 250
Long-term debt, Interest Rate		6.05%
Dalton Expansion Project
Debt Instrument [Line Items]
Proceeds from Issuance of Other Long-term Debt		$ 29,200
Long-Term Debt		257,300
Long-term debt due within one year		1,700
4%SeniorUnsecuredNotesDue2028
Debt Instrument [Line Items]
Long-term debt, Interest Rate				4.00%
Issuance of Long-Term Debt				$ 400,000
4.6%SeniorUnsecuredNotesDue2048
Debt Instrument [Line Items]
Long-term debt, Interest Rate				4.60%
Issuance of Long-Term Debt				$ 600,000
Atlantic Sunrise Project [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt Instrument, Term	20 years
Percent Of Construction Costs Capitalized	100.00%
Long-Term Debt	$ 789,900
Williams Companies Inc [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			$ 4,500,000
Commercial paper [Member] \| Williams Companies Inc [Member]
Debt Instrument [Line Items]
Commercial paper, outstanding		$ 824,000