SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Summary of Revenues Disaggregated by Type of Customer

The following table presents the Utility’s revenues disaggregated by type of customer:

	Year Ended
(in millions)	2020		2019
Electric
Revenue from contracts with customers
Residential	$	5,523	$	4,847
Commercial	4,722		4,756
Industrial	1,530		1,493
Agricultural	1,471		1,106
Public street and highway lighting	69		67
Other (1)	(130)		168
Total revenue from contracts with customers - electric	13,185		12,437
Regulatory balancing accounts (2)	673		303
Total electric operating revenue	$	13,858	$	12,740
Natural gas
Revenue from contracts with customers
Residential	$	2,517	$	2,325
Commercial	597		605
Transportation service only	1,211		1,249
Other (1)	61		123
Total revenue from contracts with customers - gas	4,386		4,302
Regulatory balancing accounts (2)	225		87
Total natural gas operating revenue	4,611		4,389
Total operating revenues	$	18,469	$	17,129

(1) This activity is primarily related to the change in unbilled revenue and amounts subject to refund, partially offset by other miscellaneous revenue items.

(2) These amounts represent revenues authorized to be billed or refunded to customers.

Schedule of Estimated Useful Lives and Balances of Utility's Property, Plant and Equipment

The Utility’s total estimated useful lives and balances of its property, plant, and equipment were as follows:

	Estimated Useful	Balance at December 31,
(in millions, except estimated useful lives)	Lives (years)	2020		2019
Electricity generating facilities (1)	5 to 75	$	13,751	$	13,189
Electricity distribution facilities	10 to 70	37,675		35,237
Electricity transmission facilities	15 to 75	15,556		14,281
Natural gas distribution facilities	20 to 60	15,133		14,236
Natural gas transmission and storage facilities	5 to 66	9,002		8,452
Construction work in progress		2,757		2,675
Other		18		18
Total property, plant, and equipment		93,892		88,088
Accumulated depreciation		(27,756)		(26,453)
Net property, plant, and equipment		$	66,136	$	61,635

(1) Balance includes nuclear fuel inventories.  Stored nuclear fuel inventory is stated at weighted-average cost.  Nuclear fuel in the reactor is expensed as it is used based on the amount of energy output.  (See Note 15 below.)

Schedule of Changes in Asset Retirement Obligations

The following table summarizes the changes in ARO liability during 2020 and 2019, including nuclear decommissioning obligations:

(in millions)	2020		2019
ARO liability at beginning of year	$	5,854	$	5,994
Liabilities incurred in the current period	268		—
Revision in estimated cash flows	53		(376)
Accretion	265		274
Liabilities settled	(28)		(38)
ARO liability at end of year	$	6,412	$	5,854

Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income

The changes, net of income tax, in PG&E Corporation’s accumulated other comprehensive income (loss) for the year ended December 31, 2020 consisted of the following:

(in millions, net of income tax)	Pension Benefits		Other Benefits		Total
Beginning balance	$	(22)	$	17	$	(5)
Other comprehensive income before reclassifications:
Unrecognized net actuarial gain (loss) (net of taxes of $162 and $66, respectively)	(417)		170		(247)
Regulatory account transfer (net of taxes of $155 and $66, respectively)	400		(170)		230
Amounts reclassified from other comprehensive income:
Amortization of prior service cost (net of taxes of $2 and $4, respectively) (1)	(4)		10		6
Amortization of net actuarial (gain) loss (net of taxes of $1 and $6, respectively) (1)	2		(15)		(13)
Regulatory account transfer (net of taxes of $1 and $2, respectively) (1)	2		5		7
Net current period other comprehensive loss	(17)		—		(17)
Ending balance	$	(39)	$	17	$	(22)

(1) These components are included in the computation of net periodic pension and other postretirement benefit costs.  (See Note 12 below for additional details.) 

The changes, net of income tax, in PG&E Corporation’s accumulated other comprehensive income (loss) for the year ended December 31, 2019 consisted of the following:

(in millions, net of income tax)	Pension Benefits		Other Benefits		Total
Beginning balance	$	(21)	$	17	$	(4)
Other comprehensive income before reclassifications:
Unrecognized net actuarial loss (net of taxes of $24 and $88, respectively)	61		227		288
Regulatory account transfer (net of taxes of $24 and $88, respectively)	(62)		(227)		(289)
Amounts reclassified from other comprehensive income:
Amortization of prior service cost (net of taxes of $2 and $4, respectively) (1)	(4)		10		6
Amortization of net actuarial loss (net of taxes of $1 and $1, respectively) (1)	2		(2)		—
Regulatory account transfer (net of taxes of $1 and $3, respectively) (1)	2		(8)		(6)
Net current period other comprehensive loss	(1)		—		(1)
Ending balance	$	(22)	$	17	$	(5)

(1) These components are included in the computation of net periodic pension and other postretirement benefit costs.  (See Note 12 below for additional details.)

Schedule of Lease Expense

The following table shows the lease expense recognized for the fixed and variable component of the Utility’s lease obligations:

	Year Ended December 31,
(in millions)	2020		2019
Operating lease fixed cost	$	679	$	686
Operating lease variable cost	1,852		1,778
Total operating lease costs	$	2,531	$	2,464

Schedule of Future Expected Operating Lease Payments

At December 31, 2020, the Utility’s future expected operating lease payments were as follows:

(in millions)	December 31, 2020
2021	$	624
2022	550
2023	257
2024	98
2025	91
Thereafter	513
Total lease payments	2,133
Less imputed interest	(397)
Total	$	1,736