CONSOLIDATED CONDENSED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
Mar. 31, 2012	Mar. 31, 2011
OPERATING ACTIVITIES:
Net income	$ 274,005	$ 202,940
Adjustment for loss from discontinued operations	55	386
Income from continuing operations	274,060	203,326
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	177,222	149,341
Provision for bad debt	2	3
Stock-based compensation	8,758	6,144
Other	2	(1)
Income from asset sales	(12,503)	(6,774)
Deferred income tax expense	100,143	95,619
Change in assets and liabilities-
Accounts receivable	(50,665)	24,476
Inventories	(7,003)	(2,441)
Prepaid expenses and other	(22,719)	4,037
Accounts payable	(12,253)	(17,287)
Accrued liabilities	(14,083)	(14,952)
Deferred income taxes	205	243
Other noncurrent liabilities	(2,289)	10,399
Net cash provided by operating activities from continuing operations	438,877	452,133
Net cash used in operating activities from discontinued operations	(55)	(386)
Net cash provided by operating activities	438,822	451,747
INVESTING ACTIVITIES:
Capital expenditures	(492,701)	(286,251)
Proceeds from asset sales	25,543	17,022
Acquisition of TerraVici Drilling Solutions		(4,000)
Net cash used in investing activities	(467,158)	(273,229)
FINANCING ACTIVITIES:
Proceeds from line of credit		10,000
Payments on line of credit		(20,000)
Dividends paid	(15,070)	(12,784)
Exercise of stock options	1,895	11,115
Tax withholdings related to net share settlements of restricted stock	(1,514)
Excess tax benefit from stock-based compensation	3,164	10,816
Net cash used in financing activities	(11,525)	(853)
Net increase (decrease) in cash and cash equivalents	(39,861)	177,665
Cash and cash equivalents, beginning of period	364,246	63,020
Cash and cash equivalents, end of period	$ 324,385	$ 240,685

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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).