Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 286,340	$ 279,459
Accounts receivable:
Trade, net of allowance for uncollectible accounts of $0	91,707	67,932
Unbilled and other	72,548	51,943
Other current assets	61,751	51,594
Total current assets	512,346	450,928
Property and equipment	2,819,932	2,785,778
Less accumulated depreciation	(1,022,138)	(959,033)
Property and equipment, net	1,797,794	1,826,745
Operating lease right-of-use assets	213,048	0
Other assets, net	90,323	70,057
Total assets	2,613,511	2,347,730
Current liabilities:
Accounts payable	79,122	54,813
Accrued liabilities	71,982	85,594
Income tax payable	0	3,829
Current maturities of long-term debt	108,468	47,252
Current operating lease liabilities	52,840	0
Total current liabilities	312,412	191,488
Long-term debt	304,932	393,063
Operating lease liabilities	164,761	0
Deferred tax liabilities	110,118	105,862
Other non-current liabilities	39,008	39,538
Total liabilities	931,231	729,951
Redeemable noncontrolling interests	3,257	0
Shareholders’ equity:
Common stock, no par, 240,000 shares authorized, 148,802 and 148,203 shares issued, respectively	1,316,805	1,308,709
Retained earnings	437,418	383,034
Accumulated other comprehensive loss	(75,200)	(73,964)
Total shareholders’ equity	1,679,023	1,617,779
Total liabilities, redeemable noncontrolling interests and shareholders’ equity	$ 2,613,511	$ 2,347,730