STATEMENTS OF CONSOLIDATED CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash Flows from Operating Activities:
Net income	$ 276	$ 261	$ 252
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	838	705	768
Amortization of deferred financing costs	14	15	16
Deferred income taxes	(34)	18	(24)
Changes in other assets and liabilities:
Accounts and notes receivable, net	(1)	3	15
Accounts receivable/payable–affiliated companies	63	(89)	37
Inventory	(1)	(7)	(21)
Accounts payable	(4)	0	(3)
Taxes receivable	53	44	(103)
Interest and taxes accrued	4	(9)	(40)
Net regulatory assets and liabilities	(110)	3	(28)
Other current assets	2	(1)	(2)
Other current liabilities	21	(40)	(19)
Other assets	(8)	(7)	11
Other liabilities	(4)	(1)	5
Other, net	1	0	(6)
Net cash provided by operating activities	1,110	895	858
Cash Flows from Investing Activities:
Capital expenditures	(862)	(929)	(804)
Decrease (increase) in notes receivable–affiliated companies	(96)	107	(107)
Decrease (increase) in restricted cash of Bond Companies	(5)	12	(7)
Other, net	(1)	1	1
Net cash used in investing activities	(964)	(809)	(917)
Cash Flows from Financing Activities:
Proceeds from long-term debt	600	200	600
Payments of long-term debt	(590)	(372)	(537)
Dividend to parent	(135)	(252)	0
Increase (decrease) in notes payable–affiliated companies	(312)	312	(3)
Cash paid for debt retirements	0	0	(1)
Debt issuance costs	(6)	0	(7)
Contribution from parent	374	0	90
Net cash provided by (used in) financing activities	(69)	(112)	142
Net Increase (Decrease) in Cash and Cash Equivalents	77	(26)	83
Cash and Cash Equivalents at Beginning of the Year	264	290	207
Cash and Cash Equivalents at End of the Year	341	264	290
Cash Payments:
Interest, net of capitalized interest	209	213	215
Income taxes	128	81	296
Non-cash transactions:
Accounts payable related to capital expenditures	$ 65	$ 69	$ 64