Regulatory Assets and Liabilities (Tables)

12 Months Ended

Dec. 31, 2019

Regulatory Assets and Liabilities Disclosure [Abstract]

Schedule of Regulatory Assets and Liabilities [Table Text Block]

Our regulatory assets and liabilities result from our application of the provisions of ASC Topic 980 and are reflected on our Balance Sheet. Current regulatory assets are included in Prepayments and other. Current regulatory liabilities are included in Exchange gas due to others. These balances are presented on our Balance Sheet on a gross basis and are recoverable or refundable over various periods. Below are the details of our regulatory assets and liabilities as of December 31, 2019 and 2018:

	2019		2018
	(Thousands of Dollars)
Current regulatory assets:
Levelized depreciation	$	978	$	414
Fuel Recovery	—		6,619
Total current regulatory assets	978		7,033
Noncurrent regulatory assets:
Grossed-up deferred taxes on equity funds used during construction	5,498		5,883
Levelized depreciation	16,437		18,109
Total noncurrent regulatory assets	21,935		23,992
Total regulatory assets	$	22,913	$	31,025
Current regulatory liabilities:
Fuel recovery	$	4,121	$	—
Noncurrent regulatory liabilities:
Postretirement benefits	37,722		36,154
Deferred federal taxes-liability	206,527		206,527
Deferred state taxes - liability	12,120		12,120
Customer tax refund	49,598		24,094
Asset retirement obligations, net	17,065		11,535
Total noncurrent regulatory liabilities	323,032		290,430
Total regulatory liabilities	$	327,153	$	290,430