CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands		Jun. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents		$ 593,284	$ 336,997
Short-term investments		43,262	28,369
Accounts receivable, net		780,247	698,477
Inventory, net		173,063	166,307
Assets held for sale		35,963	37,052
Other current assets		156,652	180,134
Total current assets		1,782,471	1,447,336
Property, plant and equipment, net		5,709,895	6,109,565
Goodwill		172,817	173,226
Deferred income taxes		406,281	419,003
Other long-term assets		228,824	252,854
Total assets (1)	[1]	8,300,288	8,401,984
Current liabilities:
Current portion of debt		243	181
Trade accounts payable		379,028	363,416
Accrued liabilities		492,787	533,044
Income taxes payable		1,724	22,835
Total current liabilities		873,782	919,476
Long-term debt		3,818,613	4,027,766
Other long-term liabilities		290,013	301,633
Deferred income taxes		20,713	10,338
Total liabilities (1)	[1]	5,003,121	5,259,213
Commitments and contingencies (Note 7)
Redeemable noncontrolling interest in subsidiary (Note 3)		208,519	203,998
Shareholders' equity:
Preferred shares, par value $0.001 per share: Series A 6% Cumulative Mandatory Convertible; $50 per share liquidation preference; issued 5,750		6
Common shares, par value $0.001 per share: Authorized common shares 800,000; issued 410,252 and 367,510, respectively		410	368
Capital in excess of par value		3,382,711	2,791,129
Accumulated other comprehensive income (loss)		(12,573)	11,185
Retained earnings		1,006,500	1,423,154
Less: treasury shares, at cost, 52,800 and 52,800 common shares, respectively		(1,314,020)	(1,314,020)
Total shareholders' equity		3,063,034	2,911,816
Noncontrolling interest		25,614	26,957
Total equity		3,088,648	2,938,773
Total liabilities and equity		$ 8,300,288	$ 8,401,984

[1] The condensed consolidated balance sheet as of June 30, 2018 and December 31, 2017 include assets and liabilities of variable interest entities. See Note 3—Joint Ventures for additional information.