Fair Value Measurements - MEC (Details) - Recurring [Member] - USD ($) $ in Millions | Jun. 30, 2018 | Dec. 31, 2017 |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash collateral, net receivable, offset against derivative positions | | $ 84 | $ 76 |
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset | | (33) | (29) |
Assets, fair value disclosure | | 3,584 | 3,945 |
Derivative liability, fair value, gross asset and right to reclaim cash, offset | | 117 | 105 |
Money market mutual funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 600 | 685 |
United States government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 184 | 176 |
International government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 4 | 5 |
Corporate obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 36 | 36 |
Municipal obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 2 | 2 |
United States companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 289 | 288 |
International companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 1,370 | 1,968 |
Investment funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 187 | 178 |
Level 1 [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Assets, fair value disclosure | | 2,631 | 3,296 |
Level 1 [Member] | Money market mutual funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 600 | 685 |
Level 1 [Member] | United States government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 184 | 176 |
Level 1 [Member] | International government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Level 1 [Member] | Corporate obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Level 1 [Member] | Municipal obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Level 1 [Member] | United States companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 289 | 288 |
Level 1 [Member] | International companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 1,370 | 1,968 |
Level 1 [Member] | Investment funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 187 | 178 |
Level 2 [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Assets, fair value disclosure | | 868 | 565 |
Level 2 [Member] | Money market mutual funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Level 2 [Member] | United States government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Level 2 [Member] | International government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 4 | 5 |
Level 2 [Member] | Corporate obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 36 | 36 |
Level 2 [Member] | Municipal obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 2 | 2 |
Level 2 [Member] | United States companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Level 2 [Member] | International companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Level 2 [Member] | Investment funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Trading Securities | | | 0 |
Level 3 [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Assets, fair value disclosure | | 118 | 113 |
Level 3 [Member] | Money market mutual funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Level 3 [Member] | United States government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Level 3 [Member] | International government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Level 3 [Member] | Corporate obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Level 3 [Member] | Municipal obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Level 3 [Member] | United States companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Level 3 [Member] | International companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Level 3 [Member] | Investment funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
Trading Securities | | | 0 |
Commodity derivative [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset | | (33) | (29) |
Derivative liability, fair value, gross asset and right to reclaim cash, offset | | 117 | 105 |
Commodity derivative [Member] | Level 1 [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Derivative asset, fair value, gross asset including not subject to master netting arrangement | | 0 | 1 |
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement | | 0 | (3) |
Commodity derivative [Member] | Level 2 [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Derivative asset, fair value, gross asset including not subject to master netting arrangement | | 46 | 42 |
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement | | (184) | (167) |
Commodity derivative [Member] | Level 3 [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Derivative asset, fair value, gross asset including not subject to master netting arrangement | | 101 | 104 |
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement | | (18) | (10) |
MidAmerican Energy Company [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash collateral, net receivable, offset against derivative positions | | 1 | 0 |
Assets, fair value disclosure | | 889 | 667 |
MidAmerican Energy Company [Member] | Money market mutual funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | [1] | 346 | 133 |
MidAmerican Energy Company [Member] | United States government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 184 | 176 |
MidAmerican Energy Company [Member] | International government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 4 | 5 |
MidAmerican Energy Company [Member] | Corporate obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 36 | 36 |
MidAmerican Energy Company [Member] | Municipal obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 2 | 2 |
MidAmerican Energy Company [Member] | United States companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 289 | 288 |
MidAmerican Energy Company [Member] | International companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 6 | 7 |
MidAmerican Energy Company [Member] | Investment funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Trading Securities | | 20 | 15 |
MidAmerican Energy Company [Member] | Level 1 [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Assets, fair value disclosure | | 845 | 619 |
MidAmerican Energy Company [Member] | Level 1 [Member] | Money market mutual funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | [1] | 346 | 133 |
MidAmerican Energy Company [Member] | Level 1 [Member] | United States government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 184 | 176 |
MidAmerican Energy Company [Member] | Level 1 [Member] | International government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
MidAmerican Energy Company [Member] | Level 1 [Member] | Corporate obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
MidAmerican Energy Company [Member] | Level 1 [Member] | Municipal obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
MidAmerican Energy Company [Member] | Level 1 [Member] | United States companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 289 | 288 |
MidAmerican Energy Company [Member] | Level 1 [Member] | International companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 6 | 7 |
MidAmerican Energy Company [Member] | Level 1 [Member] | Investment funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Trading Securities | | 20 | 15 |
MidAmerican Energy Company [Member] | Level 2 [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Assets, fair value disclosure | | 44 | 46 |
MidAmerican Energy Company [Member] | Level 2 [Member] | Money market mutual funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | [1] | 0 | 0 |
MidAmerican Energy Company [Member] | Level 2 [Member] | United States government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
MidAmerican Energy Company [Member] | Level 2 [Member] | International government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 4 | 5 |
MidAmerican Energy Company [Member] | Level 2 [Member] | Corporate obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 36 | 36 |
MidAmerican Energy Company [Member] | Level 2 [Member] | Municipal obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 2 | 2 |
MidAmerican Energy Company [Member] | Level 2 [Member] | United States companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
MidAmerican Energy Company [Member] | Level 2 [Member] | International companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
MidAmerican Energy Company [Member] | Level 2 [Member] | Investment funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Trading Securities | | 0 | |
MidAmerican Energy Company [Member] | Level 3 [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Assets, fair value disclosure | | 1 | 4 |
MidAmerican Energy Company [Member] | Level 3 [Member] | Money market mutual funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | [1] | 0 | 0 |
MidAmerican Energy Company [Member] | Level 3 [Member] | United States government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
MidAmerican Energy Company [Member] | Level 3 [Member] | International government obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
MidAmerican Energy Company [Member] | Level 3 [Member] | Corporate obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
MidAmerican Energy Company [Member] | Level 3 [Member] | Municipal obligations [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
MidAmerican Energy Company [Member] | Level 3 [Member] | United States companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
MidAmerican Energy Company [Member] | Level 3 [Member] | International companies [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Available-for-sale securities | | 0 | 0 |
MidAmerican Energy Company [Member] | Level 3 [Member] | Investment funds [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Trading Securities | | 0 | |
MidAmerican Energy Company [Member] | Commodity derivative [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Derivative asset, fair value, gross asset including not subject to master netting arrangement | | 2 | 5 |
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset | [2] | (1) | (2) |
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement | | (7) | (8) |
Derivative liability, fair value, gross asset and right to reclaim cash, offset | [2] | 2 | 2 |
MidAmerican Energy Company [Member] | Commodity derivative [Member] | Level 1 [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Derivative asset, fair value, gross asset including not subject to master netting arrangement | | 0 | 0 |
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement | | 0 | 0 |
MidAmerican Energy Company [Member] | Commodity derivative [Member] | Level 2 [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Derivative asset, fair value, gross asset including not subject to master netting arrangement | | 2 | 3 |
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement | | (7) | (9) |
MidAmerican Energy Company [Member] | Commodity derivative [Member] | Level 3 [Member] | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Derivative asset, fair value, gross asset including not subject to master netting arrangement | | 1 | 4 |
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement | | $ (2) | $ (1) |
| |
[1] | Amounts are included in cash and cash equivalents and investments and restricted cash and investments on the Balance Sheets. The fair value of these money market mutual funds approximates cost. | |
[2] | Represents netting under master netting arrangements and a net cash collateral receivable of $1 million and $- million as of June 30, 2018 and December 31, 2017, respectively. | |