INCOME TAXES (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Operating Loss Carryforwards
Amount of foreign tax credit carryforwards for income tax purposes	$ 59,400
Deferred tax asset prior to consideration of valuation allowance	48,600
Current:
Federal	84,229	$ 323,386	$ 315,820
Foreign	16,685	15,841	14,551
State	10,881	21,197	32,916
Total current	111,795	360,424	363,287
Deferred:
Federal	159,686	28,183	35,530
Foreign	(28,456)	(3,265)	(1,409)
State	350	2,206	(4,564)
Total deferred	131,580	27,124	29,557
Total provision	243,375	387,548	392,844
Amounts of domestic and foreign income before income taxes
Domestic	676,146	1,061,006	1,071,435
Foreign	(10,499)	35,308	42,862
Income (loss) from continuing operations before income taxes	665,647	1,096,314	$ 1,114,297
Deferred tax liabilities:
Property, plant and equipment	1,334,611	1,187,774
Available-for-sale securities	33,187	83,787
Other	3,928	67
Total deferred tax liabilities	1,371,726	1,271,628
Deferred tax assets:
Pension reserves	3,405	1,370
Self-insurance reserves	14,318	10,311
Net operating loss and foreign tax credit carryforwards	56,287	48,285
Financial accruals	63,560	52,289
Other	12,049	8,332
Total deferred tax assets	149,619	120,587
Valuation allowance	55,758	47,699
Net deferred tax assets	93,861	72,888
Net deferred tax liabilities	$ 1,277,865	$ 1,198,740
Effective income tax rates as compared to the U.S. Federal income tax rate
U.S. Federal income tax rate (as a percent)	35.00%	35.00%	35.00%
Effect of foreign taxes (as a percent)	(2.10%)	1.20%	1.10%
State income taxes, net of federal tax benefit (as a percent)	0.80%	1.40%	1.50%
U.S. domestic production activities (as a percent)	(1.20%)	(2.60%)	(2.10%)
Other impact of foreign operations (as a percent)	3.50%	0.60%	(0.50%)
Other (as a percent)	0.60%	(0.20%)	0.30%
Effective income tax rate (as a percent)	36.60%	35.40%	35.30%
Accrued interest and penalties related to unrecognized tax benefits	$ 11,100	$ 6,400
Reconciliation of the change in gross unrecognized tax benefits
Unrecognized tax benefits at the beginning of the period	10,747	8,129
Gross decreases - tax positions in prior periods	(706)	(4)
Gross increases - tax positions in prior periods	3,278	4,293
Gross decreases - current period effect of tax positions	(821)	(836)
Gross increases - current period effect of tax positions		4
Expiration of statute of limitations for assessments	(956)	(533)
Settlements	(331)	(306)
Unrecognized tax benefits at the end of the period	11,211	10,747	$ 8,129
Unrecognized tax benefits related to discontinued operations	2,900	$ 2,900
Uncertain tax positions
Provision for uncertain tax positions	$ 6,700
IRS Issued Regulations
Period of tax impact	4 years
Amount of the expected net tax provision related to IRS issued regulations	$ 0
Minimum
Uncertain tax positions
Reasonably possible increase in the reserve for uncertain tax positions	8,400
Maximum
Uncertain tax positions
Reasonably possible increase in the reserve for uncertain tax positions	11,000
State and Local jurisdiction
Operating Loss Carryforwards
Amount of net operating loss carryforwards for income tax purposes	6,200
Net operating loss carryforward, valuation allowance	500
Foreign jurisdiction
Operating Loss Carryforwards
Amount of net operating loss carryforwards for income tax purposes	20,700
Net operating loss carryforward, valuation allowance	6,600
Foreign tax carryforwards which more likely than not will not be utilized	$ 48,600