v3.19.3.a.u2

Accounting Policies (Narrative) (Details) $ in Thousands	3 Months Ended	12 Months Ended
Accounting Policies (Narrative) (Details) $ in Thousands	Dec. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) customer	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Jan. 01, 2019 USD ($)
Accounting Policies [Table] [Line Items]
Number of customers (more than) \| customer		1,000,000
Pretax AFUDC Rate	5.84%	3.48%	2.42%	2.73%
Composite depreciation and amortization rate	2.78%	2.96%	2.77%	2.80%
Impairment of oil and gas			$ 38,000
Regulated revenue billing cycle		19 days
Duration of cost of gas recovered or refunded		12 months
Gross revenue taxes	$ 24,200	$ 81,800	$ 82,500	$ 75,100
Right of use asset		40,004			$ 43,200
Lease liabilities		$ 59,500
Prepaid or deferred rent					15,700
ASU 2016-02
Accounting Policies [Table] [Line Items]
Right of use asset					43,200
Lease liabilities					58,900
Prepaid or deferred rent					$ 15,700

The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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The amount of regulated other operating revenues recognized during the period.

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[Line Items] for Accounting Policies [Table]

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The duration of time to be able to recover cost of gas or refund overpayments to customers.

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Number of Customers

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Lease incentives and prepaid or deferred rent - Net of ROU assets.

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Regulated revenue billing cycle in days

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WASHINGTON GAS LIGHT CO 10-K