Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
CURRENT ASSETS:
Cash, cash equivalents and restricted cash	$ 59,322	$ 32,699
Accounts receivable, net of allowance of $1,444 in 2018 and $2,445 in 2017	147,755	109,114
Inventory	33,536	22,169
Prepaid supplies and other	18,608	20,521
TOTAL CURRENT ASSETS	259,221	184,503
Property and equipment, net	1,555,005	1,159,962
Lease incentive	63,780	80,684
Other assets	57,220	25,435
Goodwill and acquired intangibles	535,359	44,577
Convertible note hedges	0	53,683
Intangibles	144,614	7,298
Goodwill	390,745	37,279
TOTAL ASSETS	2,470,585	1,548,844
CURRENT LIABILITIES:
Accounts payable	109,843	99,728
Accrued salaries, wages and benefits	50,932	40,127
Accrued expenses	19,623	10,455
Current portion of debt obligations	29,654	18,512
Unearned revenue	19,082	15,850
TOTAL CURRENT LIABILITIES	229,134	184,672
Long term debt	1,371,598	497,246
Convertible note obligations	0	54,359
Post-retirement obligations	64,485	61,355
Other liabilities	51,905	45,353
Stock Warrants	203,782	211,136
Deferred income taxes	113,243	99,444
TOTAL LIABILITIES	2,034,147	1,153,565
Commitments and contingencies (Note I)
STOCKHOLDERS’ EQUITY:
Preferred stock, 20,000,000 shares authorized, including 75,000 Series A Junior Participating Preferred Stock	0	0
Common stock, par value $0.01 per share; 110,000,000 shares authorized; 59,134,173 and 59,057,195 shares issued and outstanding in 2018 and 2017, respectively	591	591
Additional paid-in capital	471,158	471,456
Accumulated earnings (deficit)	56,051	(13,748)
Accumulated other comprehensive loss	(91,362)	(63,020)
TOTAL STOCKHOLDERS’ EQUITY	436,438	395,279
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 2,470,585	$ 1,548,844