Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 9,777	$ 20,776
Restricted cash and equivalents	3,881	3,369
Accounts receivable, net	255,805	269,153
Materials, supplies and fuel	117,172	117,299
Derivative assets, current	342	1,500
Income tax receivable, net	16,446	12,978
Regulatory assets, current	43,282	48,776
Other current assets	26,479	29,982
Total current assets	473,184	503,833
Investments	21,929	41,013
Property, plant and equipment	6,784,679	6,000,015
Less accumulated depreciation and depletion	(1,281,493)	(1,145,136)
Total property, plant and equipment, net	5,503,186	4,854,879
Other assets:
Goodwill	1,299,454	1,299,454
Intangible assets, net	13,266	14,337
Regulatory assets, non-current	228,062	235,459
Other assets, non-current	19,376	14,352
Total other assets, non-current	1,560,158	1,563,602
TOTAL ASSETS	7,558,457	6,963,327
Current liabilities:
Accounts payable	193,523	210,609
Accrued liabilities	226,767	215,501
Derivative liabilities, current	2,254	947
Regulatory liabilities, current	33,507	29,810
Notes payable	349,500	185,620
Current maturities of long-term debt	5,743	5,743
Total current liabilities	811,294	648,230
Long-term debt, net of current maturities	3,140,096	2,950,835
Deferred credits and other liabilities:
Deferred income tax liabilities, net	360,719	311,331
Regulatory liabilities, non-current	503,145	510,984
Benefit plan liabilities	154,472	145,147
Other deferred credits and other liabilities	124,662	109,377
Total deferred credits and other liabilities	1,142,998	1,076,839
Commitments and contingencies (See Notes 6, 7, 8, 9, 14, 18, 19, and 20)
Stockholders’ equity -
Common stock $1 par value; 100,000,000 shares authorized; issued: 61,480,658 and 60,048,567, respectively	61,481	60,049
Additional paid-in capital	1,552,788	1,450,569
Retained earnings	778,776	700,396
Treasury stock at cost - 3,956 and 44,253, respectively	(267)	(2,510)
Accumulated other comprehensive income (loss)	(30,655)	(26,916)
Total stockholders’ equity	2,362,123	2,181,588
Noncontrolling interest	101,946	105,835
Total equity	2,464,069	2,287,423
TOTAL LIABILITIES AND TOTAL EQUITY	$ 7,558,457	$ 6,963,327