Short-Term Debt and Credit Facilities Short-Term Debt and Credit Facilities - Credit Facilities (Details) - USD ($) $ in Millions		Dec. 31, 2015	Dec. 31, 2014
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	[1]	$ 6,421	$ 6,696
Short-term debt	[1]	974	1,445
Line of Credit Facility, Amounts Supported	[1]	415	625
Line of Credit Facility, Remaining Borrowing Capacity	[1]	5,032	4,626
Berkshire Hathaway Energy [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		2,000	2,000
Short-term debt		253	395
Line of Credit Facility, Amounts Supported		51	28
Line of Credit Facility, Remaining Borrowing Capacity		1,696	1,577
PacifiCorp [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		1,200	1,200
Short-term debt		20	20
Line of Credit Facility, Amounts Supported		160	398
Line of Credit Facility, Remaining Borrowing Capacity		1,020	782
MidAmerican Funding [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		609	609
Short-term debt		0	50
Line of Credit Facility, Amounts Supported		195	195
Line of Credit Facility, Remaining Borrowing Capacity		414	364
NV Energy [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		650	650
Short-term debt		0	0
Line of Credit Facility, Amounts Supported		0	0
Line of Credit Facility, Remaining Borrowing Capacity		650	650
Northern Powergrid Holdings [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		221	265
Short-term debt		0	215
Line of Credit Facility, Amounts Supported		0	0
Line of Credit Facility, Remaining Borrowing Capacity		221	50
AltaLink [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		813	1,119
Short-term debt		401	251
Line of Credit Facility, Amounts Supported		9	4
Line of Credit Facility, Remaining Borrowing Capacity		403	864
Other [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		928	853
Short-term debt		300	514
Line of Credit Facility, Amounts Supported		0	0
Line of Credit Facility, Remaining Borrowing Capacity		$ 628	$ 339

[1] The above table does not include unused credit facilities and letters of credit for investments that are accounted for under the equity method.