Components of Accumulated Other Comprehensive Loss, Net - MEC (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance - Accumulated other comprehensive loss, net			$ (908)
Other comprehensive income (loss), unrealized gains on available-for-sale securities	$ 80	$ (103)	151	$ 179
Other comprehensive income (loss), unrealized gains (losses) on cash flow hedges	(3)	(7)	(2)	(13)
Other comprehensive income (loss)	(39)	(412)	(110)	(303)
Ending balance - Accumulated other comprehensive loss, net	(1,018)		(1,018)
Accumulated Other Comprehensive (Loss) Income, Net [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance - unrealized gains (losses) on available-for-sale securities			615	390
Beginning balance - unrealized gains (losses) on cash flow hedges			7	18
Beginning balance - Accumulated other comprehensive loss, net			(908)	(494)
Other comprehensive income (loss), unrealized gains on available-for-sale securities			151	179
Other comprehensive income (loss), unrealized gains (losses) on cash flow hedges			(2)	(13)
Other comprehensive income (loss)			(110)	(303)
Ending balance - unrealized gains (losses) on available-for-sale securities	766	569	766	569
Ending balance - unrealized gains (losses) on cash flow hedges	5	5	5	5
Ending balance - Accumulated other comprehensive loss, net	(1,018)	(797)	(1,018)	(797)
MidAmerican Energy Company [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance - Accumulated other comprehensive loss, net			(30)
Other comprehensive income (loss), unrealized gains on available-for-sale securities	0	(1)	2	0
Other comprehensive income (loss), unrealized gains (losses) on cash flow hedges	0	(3)	0	(7)
Other comprehensive income (loss)	0	(4)	2	(7)
Dividend, unrealized losses on cash flow hedges, transfer of operations			(90)
Ending balance - Accumulated other comprehensive loss, net	(1)		(1)
MidAmerican Energy Company [Member] | Accumulated Other Comprehensive (Loss) Income, Net [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance - unrealized gains (losses) on available-for-sale securities			(3)	(3)
Beginning balance - unrealized gains (losses) on cash flow hedges			(27)	(20)
Beginning balance - Accumulated other comprehensive loss, net			(30)	(23)
Other comprehensive income (loss), unrealized gains on available-for-sale securities			2	0
Other comprehensive income (loss), unrealized gains (losses) on cash flow hedges			0	(7)
Other comprehensive income (loss)			2	(7)
Dividend, unrealized losses on cash flow hedges, transfer of operations			(27)
Ending balance - unrealized gains (losses) on available-for-sale securities	(1)	(3)	(1)	(3)
Ending balance - unrealized gains (losses) on cash flow hedges	0	(27)	0	(27)
Ending balance - Accumulated other comprehensive loss, net	$ (1)	$ (30)	$ (1)	$ (30)