Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
CURRENT ASSETS
Cash and cash equivalents	$ 9	$ 12	$ 2	$ 12
Trade receivables	193	232
Inventories	57	58
Other current assets, net	128	123
Total current assets	387	425
PROPERTY, PLANT AND EQUIPMENT	21,045	20,915
Accumulated depreciation, depletion and amortization	(15,307)	(15,030)
Total property, plant and equipment	5,738	5,885
OTHER ASSETS	29	44
TOTAL ASSETS	6,154	6,354
CURRENT LIABILITIES
Current maturities of long-term debt	100	100
Accounts payable	243	219
Accrued liabilities	264	407
Total current liabilities	607	726
LONG-TERM DEBT - PRINCIPAL AMOUNT	5,069	5,168
DEFERRED GAIN AND ISSUANCE COSTS, NET	369	397
OTHER LONG-TERM LIABILITIES	600	620
EQUITY
Preferred stock (20 million shares authorized at $0.01 par value) no shares outstanding at June 30, 2017 and December 31, 2016
Common stock (200 million shares authorized at $0.01 par value) outstanding shares (June 30,2017 - 42,772,851 and December 31, 2016 - 42,542,637)
Additional paid-in capital	4,871	4,861
Accumulated deficit	(5,399)	(5,404)
Accumulated other comprehensive loss	(11)	(14)
Total equity attributable to common stock	(539)	(557)
Noncontrolling interest	48
Total equity	(491)	(557)
TOTAL LIABILITIES AND EQUITY	$ 6,154	$ 6,354