Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
ASSETS
Cash and cash equivalents	$ 52,183	$ 37,711
Accounts receivable, net of allowance of $782 and $1,580, respectively	254,188	229,885
Prepaid expenses and other current assets	21,119	31,228
Total current assets	327,490	298,824
Property and equipment, net of accumulated depreciation of $1,475,951 and $1,352,323, respectively	2,802,449	2,837,657
Goodwill	40,927	38,386
Non-current deferred tax assets	12,814	13,735
Other assets	88,718	83,002
Total assets	3,272,398	3,271,604
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	277,804	260,107
Income taxes payable	3,034	2,086
Current portion of long-term debt	10,000	10,000
Total current liabilities	290,838	272,193
Long-term debt, net	1,437,187	1,435,169
Deferred revenue	39,735	53,437
Other liabilities	53,030	51,842
Total liabilities	1,820,790	1,812,641
Commitments and contingencies
Preferred stock – $0.01 par value; 50,000 shares authorized; none issued and outstanding at December 31, 2017 and 2016, respectively	0	0
Common stock – $0.01 par value; 300,000 shares authorized; 118,204 and 117,554 shares issued and outstanding at December 31, 2017 and 2016, respectively	1,182	1,176
Additional paid-in capital	1,794,713	1,780,350
Accumulated deficit	(344,287)	(322,563)
Total stockholders' equity	1,451,608	1,458,963
Total liabilities and stockholders' equity	$ 3,272,398	$ 3,271,604