Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 482,106	$ 494,192
Accounts receivable:
Trade, net of allowance for uncollectible accounts of $115 and $350, respectively	75,995	76,287
Unbilled revenue and other	41,570	20,465
Current deferred tax assets	15,706	53,573
Income tax receivable	9,569	0
Other current assets	54,064	39,518
Total current assets	679,010	684,035
Property and equipment	2,655,343	2,544,857
Less accumulated depreciation	(1,005,859)	(941,848)
Property and equipment, net	1,649,484	1,603,009
Other assets:
Equity investments	0	26,200
Goodwill	45,107	45,107
Other assets, net	57,945	41,608
Total assets	2,431,546	2,399,959
Current liabilities:
Accounts payable	127,733	65,370
Accrued liabilities	69,904	71,641
Income tax payable	0	2,261
Current maturities of long-term debt	70,905	71,640
Total current liabilities	268,542	210,912
Long-term debt	607,502	677,695
Deferred tax liabilities	173,901	180,974
Other non-current liabilities	44,425	51,415
Total liabilities	1,094,370	1,120,996
Commitments and contingencies
Shareholders’ equity:
Common stock, no par, 240,000 shares authorized, 120,540 and 106,289 shares issued, respectively	1,045,483	945,565
Retained earnings	377,267	404,299
Accumulated other comprehensive loss	(85,574)	(70,901)
Total shareholders’ equity	1,337,176	1,278,963
Total liabilities and shareholders’ equity	$ 2,431,546	$ 2,399,959