CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 99,635	$ 155,561
Short-term investments.	110,801
Accounts receivable, net of allowance for credit losses	133,362	137,646
Income tax receivable	1,134	1,072
Prepaid expenses and other current assets	56,831	46,382
Assets held for sale	26,052
Total current assets	427,815	340,661
Property, plant and equipment, net	2,019,444	1,760,152
Investments	109,578	111,665
Goodwill	1,013,243	1,035,274
Customer relationships, net	73,939	113,418
Other intangible assets	10,557	10,557
Other assets	58,116	135,573
Total assets	3,712,692	3,507,300
Current liabilities:
Accounts payable	40,953	25,283
Advance billings and customer deposits	53,028	49,544
Accrued compensation	68,272	74,957
Accrued interest	17,819	21,194
Accrued expense	97,417	81,931
Current portion of long-term debt and finance lease obligations	7,959	17,561
Liabilities held for sale	97
Total current liabilities	285,545	270,470
Long-term debt and finance lease obligations	2,118,853	1,932,666
Deferred income taxes	194,458	171,021
Pension and other post-retirement obligations	214,671	300,373
Convertible security interest		238,701
Contingent payment rights		123,241
Other long-term liabilities	62,789	81,600
Total liabilities	2,876,316	3,118,072
Commitments and contingencies (Note 15)
Series A preferred stock, par value $0.01 per share; 10,000,000 shares authorized, 434,266 shares outstanding as of December 31, 2021; liquidation preference of $436,943 as of December 31, 2021	288,576
Shareholders' equity:
Common stock, par value $0.01 per share; 150,000,000 and 100,000,000 shares authorized as of December 31, 2021 and December 31, 2020, respectively, 113,647,364 and 79,227,607 shares outstanding as of December 31, 2021 and December 31, 2020, respectively	1,137	792
Additional paid-in capital	740,746	525,673
Accumulated deficit	(141,599)	(34,514)
Accumulated other comprehensive loss, net	(59,571)	(109,418)
Noncontrolling interest	7,087	6,695
Total shareholders' equity	547,800	389,228
Total liabilities, mezzanine equity and shareholders' equity	$ 3,712,692	$ 3,507,300