REGULATORY ASSETS & REGULATORY LIABILITIES (Tables)

3 Months Ended

Mar. 31, 2016

Regulatory Assets and Liabilities Disclosure [Abstract]

Schedule of Regulatory Assets

Regulatory Assets consisted of the following items (in thousands):

	March 31, 2016		December 31, 2015
Environmental Remediation Costs:
Expended - Net	$	47,023	$	42,032
Liability for Future Expenditures	136,779		123,194
Deferred Asset Retirement Obligation Costs	42,515		42,430
Deferred Pension and Other Postretirement Benefit Costs	79,779		79,779
Deferred Gas Costs - Net	—		2,701
Conservation Incentive Program Receivable	19,205		2,624
Deferred Interest Rate Contracts	9,379		7,631
Energy Efficiency Tracker	—		496
Pipeline Supplier Service Charges	3,360		3,776
Pipeline Integrity Cost	4,310		4,596
AFUDC - Equity Related Deferrals	11,638		11,423
Other Regulatory Assets	2,974		2,752
Total Regulatory Assets	$	356,962	$	323,434

Schedule of Regulatory Liabilities

Regulatory Liabilities consisted of the following items (in thousands):

	March 31, 2016		December 31, 2015
Excess Plant Removal Costs	$	32,294	$	32,644
Deferred Revenues - Net	11,241		—
Societal Benefit Costs	9,454		10,197
Energy Efficiency Tracker	2,384		—
Total Regulatory Liabilities	$	55,373	$	42,841