Supplementary Financial Information (Summary of Investments And Other Property) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Supplementary Financial Information [Abstract]
Assets related to employee benefit plans	$ 133		$ 133
Land	20		20
Other	2		2
Total investments and other property	$ 155	$ 155	$ 155

Investment Assets Related To Employee Benefit Plans, Including Employee Savings

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- Definition

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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- Definition

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

+ References

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- References

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- Definition

Amount of long-term investments classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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