Subsidiary Debt Subsidiary Debt - AltaLink (Details) - USD ($) $ in Millions		Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Par value		$ 39,634
Subsidiary Debt [Member]
Debt Instrument [Line Items]
Par value		30,883
Other long-term debt		30,672	$ 27,573
ALP Investments [Member]
Debt Instrument [Line Items]
Par value	[1]	308
Other long-term debt		308	442
ALP Investments [Member] | Series 12-1 Senior Bonds, 3.674%, due 2019 [Member]
Debt Instrument [Line Items]
Par value	[1]	0
Other long-term debt		0	148
ALP Investments [Member] | Series 13-1 Senior Bonds, 3.265%, due 2020 [Member]
Debt Instrument [Line Items]
Par value	[1]	154
Other long-term debt		154	148
ALP Investments [Member] | Series 15-1 Senior Bonds, 2.244%, due 2022 [Member]
Debt Instrument [Line Items]
Par value	[1]	154
Other long-term debt		$ 154	$ 146
ALP Investments [Member] | Subsidiary Debt [Member] | Series 12-1 Senior Bonds, 3.674%, due 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		3.674%	3.674%
ALP Investments [Member] | Subsidiary Debt [Member] | Series 13-1 Senior Bonds, 3.265%, due 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		3.265%	3.265%
ALP Investments [Member] | Subsidiary Debt [Member] | Series 15-1 Senior Bonds, 2.244%, due 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		2.244%	2.244%
AltaLink, L.P. [Member] | Subsidiary Debt [Member]
Debt Instrument [Line Items]
Par value	[1]	$ 3,576
Other long-term debt		$ 3,564	$ 3,392
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2013-2 Notes, 3.621%, due 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		3.621%	3.621%
Par value	[1]	$ 96
Other long-term debt		$ 96	$ 92
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2012-2 Notes, 2.978%, due 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		2.978%	2.978%
Par value	[1]	$ 212
Other long-term debt		$ 212	$ 201
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2013-4 Notes, 3.668%, due 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		3.668%	3.668%
Par value	[1]	$ 385
Other long-term debt		$ 384	$ 366
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2014-1 Notes, 3.399%, due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		3.399%	3.399%
Par value	[1]	$ 269
Other long-term debt		$ 269	$ 256
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2016-1 Notes, 2.747%, due 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		2.747%	2.747%
Par value	[1]	$ 269
Other long-term debt		$ 269	$ 255
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2006-1 Notes, 5.249%, due 2036 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		5.249%	5.249%
Par value	[1]	$ 115
Other long-term debt		$ 115	$ 109
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2010-1 Notes, 5.381%, due 2040 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		5.381%	5.381%
Par value	[1]	$ 96
Other long-term debt		$ 96	$ 91
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2010-2 Notes, 4.872%, due 2040 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		4.872%	4.872%
Par value	[1]	$ 115
Other long-term debt		$ 115	$ 109
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2011-1 Notes, 4.462%, due 2041 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		4.462%	4.462%
Par value	[1]	$ 212
Other long-term debt		$ 211	$ 201
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2012-1 Notes, 3.99%, due 2042 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		3.99%	3.99%
Par value	[1]	$ 404
Other long-term debt		$ 398	$ 380
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2013-3 Notes, 4.922%, due 2043 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		4.922%	4.922%
Par value	[1]	$ 269
Other long-term debt		$ 268	$ 256
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2014-3 Notes, 4.054%, due 2044 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		4.054%	4.054%
Par value	[1]	$ 227
Other long-term debt		$ 226	$ 215
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2015-1 Notes, 4.090%, due 2045 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		4.09%	4.09%
Par value	[1]	$ 269
Other long-term debt		$ 268	$ 255
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2016-2 Notes, 3.717%, due 2046 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		3.717%	3.717%
Par value	[1]	$ 346
Other long-term debt		$ 345	$ 328
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2013-1 Notes, 4.446%, due 2053 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		4.446%	4.446%
Par value	[1]	$ 192
Other long-term debt		$ 192	$ 183
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Series 2014-2 Notes, 4.274%, due 2064 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		4.274%	4.274%
Par value	[1]	$ 100
Other long-term debt		$ 100	$ 95
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Construction Loan, 4.950%, due 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			5.66%
AltaLink, L.P. [Member] | Subsidiary Debt [Member] | Construction Loan, 5.620%, due 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		5.62%
Par value	[1]	$ 7
Other long-term debt		7	$ 8
BHE Transmission [Member] | Subsidiary Debt [Member]
Debt Instrument [Line Items]
Par value	[1]	3,891
Other long-term debt		$ 3,879	$ 3,842

[1] ns): Par Value(1) 2019 2018AltaLink Investments, L.P.: Series 12-1 Senior Bonds, 3.674%, due 2019$— $— $148Series 13-1 Senior Bonds, 3.265%, due 2020154 154 148Series 15-1 Senior Bonds, 2.244%, due 2022154 154 146Total AltaLink Investments, L.P.308 308 442 AltaLink, L.P.: Series 2013-2 Notes, 3.621%, due 202096 96 92Series 2012-2 Notes, 2.978%, due 2022212 212 201Series 2013-4 Notes, 3.668%, due 2023385 384 366Series 2014-1 Notes, 3.399%, due 2024269 269 256Series 2016-1 Notes, 2.747%, due 2026269 269 255Series 2006-1 Notes, 5.249%, due 2036115 115 109Series 2010-1 Notes, 5.381%, due 204096 96 91Series 2010-2 Notes, 4.872%, due 2040115 115 109Series 2011-1 Notes, 4.462%, due 2041212 211 201Series 2012-1 Notes, 3.990%, due 2042404 398 380Series 2013-3 Notes, 4.922%, due 2043269 268 256Series 2014-3 Notes, 4.054%, due 2044227 226 215Series 2015-1 Notes, 4.090%, due 2045269 268 255Series 2016-2 Notes, 3.717%, due 2046346 345 328Series 2013-1 Notes, 4.446%, due 2053192 192 183Series 2014-2 Notes, 4.274%, due 2064100 100 95Total AltaLink, L.P.3,576 3,564 3,392 Other: Construction Loan, 5.620%, due 20207 7 8 Total BHE Transmission$3,891 $3,879 $3,842(1)The par values for these debt instruments are denominated in Canadian dollars.