Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Cash Flows from Operating Activities:
Net Income	$ 14,743	$ 22,946
Adjustments to reconcile net income to net cash provided by operation activities -
Depreciation, depletion, and amortization	201,072	187,503
Accretion of asset retirement obligation	4,246	4,732
Deferred income taxes	13,507	15,235
Stock-based compensation expenses	5,571	8,454
Other Noncash Income (Expense)	(390)	(4,093)
(Increase) Decrease in accounts receivable	14,159	(3,293)
Increase (decrease) in accounts payable and accrued liabilities	7,299	2,588
Increase (decrease) in income taxes payable	543	(208)
Increase (decrease) in accrued interest	(8,575)	(8,257)
Net Cash Provided by Operating Activities	252,175	225,607
Cash Flows from Investing Activities:
Additions to property and equipment	(316,972)	(435,722)
Proceeds from the sale of property and equipment	145,535	6,990
Transfer of company funds from restricted cash	6,501	0
Transfer of company funds to restricted cash	(18,345)	0
Net Cash Used in Investing Activities	(183,281)	(428,732)
Cash Flows from Financing Activities:
Proceeds from bank borrowings	639,000	968,500
Payments of bank borrowings	(702,000)	(764,900)
Net proceeds from issuances of common stock	824	946
Purchase of treasury shares	(954)	(1,494)
Net Cash Used in Financing Activities	(63,130)	203,052
Net Increase (Decrease) in Cash and Cash Equivalents	5,764	(73)
Cash and Cash Equivalents at Beginning of Period	3,277	170
Cash and Cash Equivalents at End of Period	9,041	97
Supplemental Disclosures of Cash Flows Information:
Cash paid during period for interest, net of amounts capitalized	61,983	57,990
Cash paid during period for income taxes	$ 150	$ 208