CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Cash flows from continuing operating activities
Net income (loss)	$ 11,641	$ (68)
Adjustments to reconcile net income (loss) to net cash provided (used) by continuing operating activities:
Net loss from discontinued operations	2
Deferred income taxes	5,999	340
Gains on property insurance recoveries associated with property, plant and equipment	(5,147)
Depreciation, depletion and amortization of property, plant and equipment	8,679	6,550
Other	(113)	619
Cash provided (used) by changes in assets and liabilities (net of effects of discontinued operations):
Accounts receivable	(9,876)	(9,796)
Inventories	150	(5,368)
Prepaid and accrued income taxes	8,247	(10,909)
Other supplies, prepaid items and other	3,540	2,212
Accounts payable	8,179	(4,695)
Other current and noncurrent liabilities	(9,612)	(4,128)
Deferred gain on insurance recoveries	(1,383)	5,122
Net cash provided (used) by continuing operating activities	20,306	(20,121)
Cash flows from continuing investing activities
Expenditures for property, plant and equipment	(45,308)	(44,344)
Proceeds from property insurance recovery associated with property, plant and equipment	5,147	4,495
Proceeds from sales of property and equipment	78	199
Deposits of current and noncurrent restricted cash and cash equivalents	(165,106)	(82)
Proceeds from noncurrent restricted investments	209,990
Proceeds from sales of carbon credits	1,536
Payments on contractual obligations-carbon credits	(1,245)
Other assets	17	(109)
Net cash provided (used) by continuing investing activities	5,109	(39,841)
Cash flows from continuing financing activities
Proceeds from long-term debt, net of fees		34,825
Payments on long-term debt	(2,322)	(1,738)
Payments on short-term financing	(4,073)	(2,782)
Proceeds from exercise of stock options	78	249
Excess income tax benefit associated with stock-based compensation	300	110
Dividends paid on preferred stocks	(300)
Net cash provided (used) by continuing financing activities	(6,317)	30,664
Cash flows of discontinued operations:
Operating cash flows	(65)	(52)
Net increase (decrease) in cash and cash equivalents	19,033	(29,350)
Cash and cash equivalents at beginning of period	143,750	98,020
Cash and cash equivalents at end of period	$ 162,783	$ 68,670