CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS (UNAUDITED) (USD $)	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Cash flows provided by (used in) operating activities:
Net earnings	$ 120,435,000	$ 131,349,000
Adjustments to reconcile net earnings to net cash flows provided by (used in) operating activities:
Depreciation and amortization	118,622,000	112,753,000
Deferred income taxes	51,543,000	60,087,000
Provision for bad debts	9,864,000	9,562,000
Unrealized (gain) loss on commodity derivatives	14,413,000	(16,654,000)
Share-based compensation expense	4,899,000	4,454,000
Earnings from unconsolidated investments	(50,249,000)	(42,396,000)
Changes in operating assets and liabilities	81,384,000	(16,663,000)
Net cash flows provided by operating activities	350,911,000	242,492,000
Cash flows provided by (used in) investing activities:
Additions to property, plant and equipment	(143,902,000)	(129,379,000)
Loan to unconsolidated investments	(72,000,000)	0
Plant retirements and other	(488,000)	359,000
Net cash flows used in investing activities	(216,390,000)	(129,020,000)
Cash flows provided by (used in) financing activities:
Increase (decrease) in book overdraft	4,877,000	(12,030,000)
Issuance of long-term debt	0	857,000
Renewal cost for credit facilities	(2,138,000)	(5,831,000)
Dividends paid on common stock	(37,390,000)	(37,322,000)
Dividends paid on preferred stock	0	(4,341,000)
Repayment of long-term debt obligation	(278,000)	(140,723,000)
Net change in revolving credit facilities	(101,572,000)	76,095,000
Other	1,694,000	1,866,000
Net cash flows provided by (used in) financing activities	(134,807,000)	(121,429,000)
Change in cash and cash equivalents	(286,000)	(7,957,000)
Cash and cash equivalents at beginning of period	3,299,000	10,545,000
Cash and cash equivalents at end of period	$ 3,013,000	$ 2,588,000

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).