CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Assets
Cash and cash equivalents	$ 141,646	$ 258,986
Restricted cash	5,000	9,033
Accounts and notes receivable
Customers, less allowance for doubtful accounts 2017 — $2,649; 2016 — $2,813	434,089	398,488
Other	154,248	93,333
Inventories	384,338	345,616
Prepaid expenses	60,780	31,726
Total current assets	1,180,101	1,137,182
Investments and long-term receivables	35,115	39,226
Property, plant & equipment, net	3,918,931	3,261,438
Goodwill	3,122,321	3,094,824
Other intangible assets, net	1,063,630	769,052
Other noncurrent assets	184,793	169,753
Total assets	9,504,891	8,471,475
Liabilities
Current maturities of long-term debt	41,383	138
Short-term debt	0	0
Trade payables and accruals	197,335	145,042
Accrued salaries, wages and management incentives	87,208	91,455
Accrued interest	11,664	9,751
Other current liabilities	105,282	125,858
Total current liabilities	442,872	372,244
Long-term debt	2,813,482	1,982,751
Deferred income taxes, net	464,081	702,854
Deferred management incentive and other compensation	19,856	19,698
Pension benefits	245,449	247,784
Other postretirement benefits	37,856	39,533
Asset retirement obligations	218,117	223,872
Deferred revenue	191,476	198,388
Other noncurrent liabilities	102,809	111,875
Total liabilities	4,535,998	3,898,999
Other commitments and contingencies (Note 12)
Equity
Common stock, $1 par value, Authorized 480,000 shares, Outstanding 132,324 and 132,339 shares, respectively	132,324	132,339
Capital in excess of par value	2,805,587	2,807,995
Retained earnings	2,180,448	1,771,518
Accumulated other comprehensive loss	(149,466)	(139,376)
Total equity	4,968,893	4,572,476
Total liabilities and equity	$ 9,504,891	$ 8,471,475