REGULATORY ASSETS AND LIABILITIES (Tables)

6 Months Ended

Jun. 30, 2012

Regulatory Assets and Liabilities Disclosure [Abstract]

Schedule of Regulatory Assets

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

	June 30, 2012		December 31, 2011
Environmental Remediation Costs:
Expended - Net	$	39,747	$	45,815
Liability for Future Expenditures	88,853		89,984
Deferred Asset Retirement Obligation Costs	25,319		25,162
Deferred Pension and Other Postretirement Benefit Costs	88,435		88,624
Deferred Gas Costs - Net	5,197		22,441
Conservation Incentive Program Receivable	31,498		13,580
Societal Benefit Costs Receivable	11,215		8,618
Premium for Early Retirement of Debt	456		537
Deferred Interest Rate Contracts (Note 11)	8,680		8,146
Energy Efficiency Tracker	11,650		8,464
Other Regulatory Assets	5,206		3,850
Total Regulatory Assets	$	316,256	$	315,221

Schedule of Regulatory Liabilities

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

	June 30, 2012		December 31, 2011
Excess Plant Removal Costs	$	46,668	$	47,230
Other Regulatory Liabilities	1,278		1,081
Total Regulatory Liabilities	$	47,946	$	48,311