Regulatory assets and liabilities

12 Months Ended

Dec. 31, 2020

Regulatory Assets and Liabilities Disclosure [Abstract]

Regulatory Assets and Liabilities

The following table summarizes the individual components of unamortized regulatory assets and liabilities as of December 31:


	Estimated Recovery or Refund Period	*	2020		2019
			(In thousands)
Regulatory assets:
Current:
Natural gas costs recoverable through rate adjustments	Up to 1 year		$	42,481	$	42,823
Cost recovery mechanisms	Up to 1 year		10,645		6,288
Conservation programs	Up to 1 year		7,117		6,963
Other	Up to 1 year		8,284		7,539
			68,527		63,613
Noncurrent:
Pension and postretirement benefits	**		155,942		157,069
Plant costs/asset retirement obligations	Over plant lives		71,740		66,000
Plant to be retired	-		65,919		32,931
Manufactured gas plant sites remediation	-		26,429		15,126
Natural gas costs recoverable through rate adjustments	Up to 2 years		21,539		46,381
Cost recovery mechanisms	Up to 10 years		16,245		13,108
Taxes recoverable from customers	Over plant lives		10,785		11,486
Long-term debt refinancing costs	Up to 40 years		4,426		4,286
Other	Up to 18 years		6,356		7,397
			379,381		353,784
Total regulatory assets			$	447,908	$	417,397
Regulatory liabilities:
Current:
Natural gas costs refundable through rate adjustments	Up to 1 year		$	18,565	$	23,825
Electric fuel and purchased power deferral	Up to 1 year		3,667		5,824
Taxes refundable to customers	Up to 1 year		3,557		3,472
Other	Up to 1 year		5,661		9,814
			31,450		42,935
Noncurrent:
Taxes refundable to customers	Over plant lives		227,850		246,034
Plant removal and decommissioning costs	Over plant lives		167,171		173,722
Pension and postretirement benefits	**		16,989		18,065
Other	Up to 21 years		16,065		9,549
			428,075		447,370
Total regulatory liabilities			$	459,525	$	490,305
Net regulatory position			$	(11,617)	$	(72,908)

*Estimated recovery or refund period for amounts currently being recovered or refunded in rates to customers.

** Recovered as expense is incurred or cash contributions are made.

As of December 31, 2020 and 2019, approximately $332.5 million and $276.5 million, respectively, of regulatory assets were not earning a rate of return but are expected to be recovered from customers in future rates. These assets are largely comprised of the unfunded portion of pension and postretirement benefits, asset retirement obligations, accelerated depreciation on plant to be retired and the estimated future cost of manufactured gas plant site remediation.

In 2019, the Company experienced increased natural gas costs in Washington from the rupture of the Enbridge pipeline in Canada in late 2018. As a result, the Company requested, and the WUTC approved, recovery of the balance of natural gas costs recoverable related to this period of time over three years rather than its normal one-year recovery period.

In February 2019, the Company announced that it intends to retire one aging coal-fired electric generating unit in March 2021 and two units in early 2022. The Company has accelerated the depreciation related to these facilities in property, plant and equipment and has recorded the difference between the accelerated depreciation, in accordance with GAAP, and the depreciation approved for rate-making purposes as regulatory assets. The Company expects to recover the regulatory assets related to the plants to be retired in future rates.

If, for any reason, the Company's regulated businesses cease to meet the criteria for application of regulatory accounting for all or part of their operations, the regulatory assets and liabilities relating to those portions ceasing to meet such criteria would be removed from the balance sheet and included in the statement of income or accumulated other comprehensive income (loss) in the period in which the discontinuance of regulatory accounting occurs.