REGULATORY ASSETS, LIABILITIES, AND BALANCING ACCOUNTS

Regulatory Assets and Liabilities

Current Regulatory Assets

At March 31, 2018 and December 31, 2017, the Utility had current regulatory assets of $646 million and $615 million, which included $444 million and $426 million, respectively, of costs related to CEMA fire prevention and vegetation management.

Long-Term Regulatory Assets

Long-term regulatory assets are comprised of the following:



	Asset Balance at
(in millions)	March 31, 2018		December 31, 2017
Pension benefits	$	1,915	$	1,954
Environmental compliance costs	749		837
Utility retained generation	308		319
Price risk management	68		65
Unamortized loss, net of gain, on reacquired debt	88		79
Catastrophic event memorandum account	314		274
Other	282		265
Total long-term regulatory assets	$	3,724	$	3,793

Long-Term Regulatory Liabilities

Long-term regulatory liabilities are comprised of the following:



	Liability Balance at
(in millions)	March 31, 2018		December 31, 2017
Cost of removal obligations	$	5,674	$	5,547
Deferred income taxes	873		1,021
Recoveries in excess of AROs	533		624
Public purpose programs	591		590
Other	915		897
Total long-term regulatory liabilities	$	8,586	$	8,679

For more information, see Note 3 of the Notes to the Consolidated Financial Statements in Item 8 of the 2017 Form 10-K.

Regulatory Balancing Accounts

Current regulatory balancing accounts receivable and payable are comprised of the following:



	Receivable Balance at
(in millions)	March 31, 2018		December 31, 2017
Electric distribution	$	176	$	—
Electric transmission	125		139
Utility generation	203		—
Gas distribution and transmission	269		486
Energy procurement	1		71
Public purpose programs	115		103
Other	478		423
Total regulatory balancing accounts receivable	$	1,367	$	1,222



	Payable Balance at
(in millions)	March 31, 2018		December 31, 2017
Electric distribution	$	—	$	72
Electric transmission	108		120
Utility generation	—		14
Energy procurement	265		149
Public purpose programs	491		452
Other	400		313
Total regulatory balancing accounts payable	$	1,264	$	1,120

For more information, see Note 3 of the Notes to the Consolidated Financial Statements in Item 8 of the 2017 Form 10-K.