CONSOLIDATED CONDENSED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2011	Dec. 31, 2010
OPERATING ACTIVITIES:
Net income	$ 144,286	$ 104,150
Adjustment for loss from discontinued operations	11	215
Income from continuing operations	144,297	104,365
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	86,288	73,180
Provision for bad debt	2	1
Stock-based compensation	3,922	3,187
Other		(1)
Income from asset sales	(4,683)	(2,669)
Deferred income tax expense	57,585	42,080
Change in assets and liabilities-
Accounts receivable	(34,851)	45,259
Inventories	(4,500)	(285)
Prepaid expenses and other	(24,440)	4,910
Accounts payable	18,383	(24,583)
Accrued liabilities	791	(15,072)
Deferred income taxes	113	231
Other noncurrent liabilities	(6,258)	8,267
Net cash provided by operating activities from continuing operations	236,649	238,870
Net cash used in operating activities from discontinued operations	(11)	(215)
Net cash provided by operating activities	236,638	238,655
INVESTING ACTIVITIES:
Capital expenditures	(256,943)	(116,224)
Proceeds from asset sales	10,155	3,028
Acquisition of TerraVici Drilling Solutions		(4,000)
Net cash used in investing activities	(246,788)	(117,196)
FINANCING ACTIVITIES:
Proceeds from line of credit		10,000
Payments on line of credit		(20,000)
Dividends paid	(7,522)	(6,376)
Exercise of stock options	373	2,988
Tax withholdings related to net share settlements of restricted stock	(1,514)
Excess tax benefit from stock-based compensation	2,426	2,733
Net cash used in financing activities	(6,237)	(10,655)
Net increase (decrease) in cash and cash equivalents	(16,387)	110,804
Cash and cash equivalents, beginning of period	364,246	63,020
Cash and cash equivalents, end of period	$ 347,859	$ 173,824

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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).