Change in KGS tax reform regulatory liability

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The estimated amortization period for recovery of the individual regulatory asset/liability in a schedule of regulatory assets/liabilities.

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Kansas Gas Service tax reform regulatory liability

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No definition available.

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The net amount of all current regulatory assets less all current regulatory liabilities as of the end of the period.

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No definition available.

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The net amount of noncurrent regulatory assets less all noncurrent regulatory liabilities as of the end of the period.

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- Definition

Oklahoma Natural Gas tax reform regulatory liability

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No definition available.

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Oklahoma Natural Gas tax reform regulatory liability as adjusted

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No definition available.

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- Definition

Reduction in income tax expense for the amortization of the regulatory liability associated with excess ADIT that was returned to customers

+ References

No definition available.

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- Definition

Reduction to revenues due to the change in tax rates collected in our rates as a result of the Tax Cuts and Jobs Act of 2017

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No definition available.

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[Line Items] for Tabular disclosure of assets and liabilities that result from rate actions of a regulator. Regulatory assets are created when regulatory agencies permit public utilities to defer certain costs included in rate-setting to the balance sheet. Rate actions of a regulator can impose a liability on a regulated enterprise resulting in a regulatory liability.

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No definition available.

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Texas Gas Service one-time refunds related to tax reform

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The periodic expense to reduce the value of the rate deferral asset that is created when utilities under bill customers during periods of rate increases by deferring rate increases. These customers eventually pay higher rates to repay the utility for the rate deferral.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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The net amount of all regulatory assets less all regulatory liabilities as of the end of the period.

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The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost.

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

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The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

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The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period.

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The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.

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REGULATORY ASSETS AND LIABILITIES (Details) - USD ($) $ in Thousands	3 Months Ended			12 Months Ended
	Mar. 31, 2019	Sep. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jun. 30, 2019	Jan. 31, 2019
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Federal Statutory Income Tax Rate				21.00%	21.00%	35.00%
Regulatory Assets, Current				$ 47,440	$ 54,420
Regulatory Assets, Noncurrent				391,036	437,479
Regulatory Liability, Current				(45,201)	(48,394)
Regulatory Liability, Noncurrent				(503,518)	(520,866)
Net regulatory assets and liabilities, current				2,239	6,026
Net regulatory assets and liabilities, noncurrent				(112,482)	(83,387)
Net Regulatory Assets				(110,243)	(77,361)
Amortization of Rate Deferral				2,500	1,700	$ 1,000
Reduction to revenues due to the change in tax rates collected in our rates					36,600
Oklahoma Natural Gas tax reform regulatory liability								$ 15,800
Oklahoma Natural Gas tax reform regulatory liability as adjusted								$ 15,600
Change in KGS tax reform regulatory liability	$ 2,400		$ 14,200
Kansas Gas Service tax reform regulatory liability							$ 16,600
Texas Gas Service one-time refunds related to tax reform		$ 6,600
Reduction in income tax expense for the amortization of the regulatory liability associated with excess ADIT that was returned to customers				12,800
Federal income tax rate changes [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Liability, Current				(10,297)	(30,934)
Regulatory Liability, Noncurrent				(503,518)	(520,866)
Regulatory Liabilities				$ (513,815)	$ (551,800)
Weather normalization [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Asset, Amortization Period				1 year	1 year
Regulatory Liability, Current				$ (7,281)	$ (3,792)
Regulatory Liability, Noncurrent				0	0
Regulatory Liabilities				$ (7,281)	$ (3,792)
Over-recovered purchased-gas costs [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Asset, Amortization Period				1 year	1 year
Regulatory Liability, Current				$ (27,623)	$ (13,668)
Regulatory Liability, Noncurrent				0	0
Regulatory Liabilities				(27,623)	(13,668)
Total regulated liabilities [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Liability, Current				(45,201)	(48,394)
Regulatory Liability, Noncurrent				(503,518)	(520,866)
Regulatory Liabilities				$ (548,719)	$ (569,260)
Under-recovered purchased-gas costs [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Asset, Amortization Period				1 year	1 year
Regulatory Assets, Current				$ 17,172	$ 25,083
Regulatory Assets, Noncurrent				0	0
Regulatory Assets				17,172	25,083
Pension and postretirement benefit costs [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Assets, Current				21,213	23,384
Regulatory Assets, Noncurrent				373,266	421,726
Regulatory Assets				$ 394,479	$ 445,110
Reacquired debt costs [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Asset, Amortization Period				8 years	9 years
Regulatory Assets, Current				$ 812	$ 812
Regulatory Assets, Noncurrent				5,677	6,487
Regulatory Assets				$ 6,489	$ 7,299
MGP Costs [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Asset, Amortization Period				15 years	15 years
Regulatory Assets, Current				$ 98	$ 0
Regulatory Assets, Noncurrent				9,709	7,724
Regulatory Assets				$ 9,807	$ 7,724
Ad valorem tax [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Asset, Amortization Period				1 year	1 year
Regulatory Assets, Current				$ 2,921	$ 1,070
Regulatory Assets, Noncurrent				0	0
Regulatory Assets				$ 2,921	$ 1,070
Other regulatory assets [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Asset, Amortization Period				1 to 19 years	1 to 20 years
Regulatory Assets, Current				$ 5,224	$ 4,071
Regulatory Assets, Noncurrent				2,384	1,542
Regulatory Assets				7,608	5,613
Total regulatory assets, net of amortization [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Assets, Current				47,440	54,420
Regulatory Assets, Noncurrent				391,036	437,479
Regulatory Assets				$ 438,476	$ 491,899