Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Current assets:
Cash and cash equivalents	$ 71,966	$ 53,948	$ 41,659
Receivables, net	890,579	722,945	743,687
Inventories	325,944	287,309	278,239
Prepayments and other current assets	155,893	119,500	52,035
Current assets held for sale	428	430	572
Total current assets	1,444,810	1,184,132	1,116,192
Investments	145,746	138,620	140,053
Property, plant and equipment	7,625,654	7,397,321	6,975,919
Less accumulated depreciation, depletion and amortization	2,903,274	2,818,644	2,758,163
Net property, plant and equipment	4,722,380	4,578,677	4,217,756
Deferred charges and other assets:
Goodwill	679,395	664,922	642,374
Other intangible assets, net	11,323	10,815	4,190
Operating lease right-of-use assets (Note 11)	118,795	0	0
Other	466,957	408,857	409,407
Noncurrent assets held for sale	2,087	2,087	3,998
Total deferred charges and other assets	1,278,557	1,086,681	1,059,969
Total assets	7,591,493	6,988,110	6,533,970
Current liabilities:
Short-term borrowings	89,983	0	0
Long-term debt due within one year	51,822	251,854	109,199
Accounts payable	356,059	358,505	330,926
Taxes payable	46,731	41,929	47,803
Dividends payable	40,225	39,695	38,714
Accrued compensation	71,508	69,007	53,933
Current operating lease liabilities (Note 11)	31,615	0	0
Other accrued liabilities	218,442	221,059	208,696
Current liabilities held for sale	6,217	4,001	11,713
Total current liabilities	912,602	986,050	800,984
Long-term debt	2,327,984	1,856,841	1,743,711
Deferred credits and other liabilities:
Deferred income taxes	457,588	430,085	362,896
Noncurrent operating lease liabilities (Note 11)	87,172	0	0
Other	1,145,846	1,148,359	1,175,301
Total deferred credits and other liabilities	1,690,606	1,578,444	1,538,197
Commitments and contingencies
Stockholders' equity:
Authorized - 500,000,000 shares, $1.00 par value Shares issued - 199,539,110 at June 30, 2019, 196,557,245 at June 30, 2018 and 196,564,907 at December 31, 2018	199,539	196,565	196,557
Other paid-in capital	1,315,511	1,248,576	1,245,858
Retained earnings	1,185,967	1,163,602	1,056,424
Accumulated other comprehensive loss	(37,090)	(38,342)	(44,135)
Treasury stock at cost - 538,921 shares	(3,626)	(3,626)	(3,626)
Total stockholders' equity	2,660,301	2,566,775	2,451,078
Total liabilities and stockholders' equity	$ 7,591,493	$ 6,988,110	$ 6,533,970