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COMMITMENTS AND CONTINGENCIES - Part 2 (Details) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2018 USD ($) | Dec. 31, 2016 | Dec. 31, 2017 USD ($) | Jan. 01, 2017 USD ($)
Commitments and Contingencies [Line Items] |  |  |  |
Number Of Former Manufactured Gas Sites Where We Own Or Retain Legal Responsibility For Environmental Conditions | 12 |  |  |
Number of MGP sites for which a remediation reserve was recorded | 1 |  |  |
Deferred MGP Costs, Maximum |  |  | $ 15,000 |
Regulatory assets | $ 437,479 |  | $ 405,189 |
Number of sites with ongoing groundwater monitoring | 8 |  |  |
Environmental Reserve Estimate Range, Low | 5.6 | 4 |  |
Environmental Reserve Estimate Range, High | 7.0 | 7 |  |
Accrual for Environmental Loss Contingencies, Revision in Estimates | $ 1,600 |  |  |
Environmental Reserve Estimate, Actual | 5.6 |  |  |
Percentage yield of high consequence pipeline areas |  |  | 30.00% |
MGP Costs [Member] |  |  |  |
Commitments and Contingencies [Line Items] |  |  |  |
Regulatory assets | $ 7,724 |  | $ 6,104 | $ 5,900

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- Definition The maximum amount of MGP costs (costs necessary for investigation and remediation at our 12 former MGP sites), incurred after January 1, 2017, that KGS has the KCC’s approval to defer and seek recovery of. + References No definition available. + Details
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- Definition Number of former manufactured gas sites where we own or retain legal responsibility. + References No definition available. + Details
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- Definition Minimum percentage yield required to test pipelines previously untested in high-consequence areas. + References No definition available. + Details
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- Definition Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 5.Y.Q2) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
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