Condensed Consolidating Financial Statements of Guarantors (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2013	Sep. 30, 2012
Condensed Consolidating Financial Statements of Guarantors
Ownership percentage in subsidiary	100.00%
Current Assets
Other current assets	$ 76,097		$ 78,579
Total current assets	1,258,186		1,212,399
Other assets	62,300		68,234
Total assets	5,122,704		5,073,316
Current liabilities:
Total current liabilities	479,923		479,202
Deferred income taxes	747,631		751,419
Total liabilities	3,450,456		3,448,477
Stockholder's equity:
Capital in excess of par	1,558,546		1,556,926
Retained earnings	114,005		81,497
Accumulated other comprehensive income (loss)	(303)	(18,565)	(13,584)	(18,594)
Total stockholder's equity	1,672,248		1,624,839
Total liabilities and stockholder's equity	5,122,704		5,073,316
Statements of income and comprehensive income
Total other income (expense)	(33,828)	(36,685)
Income before income taxes	80,353	68,440
Provision for income taxes	26,532	23,269
Net Income	53,821	45,171
Change in fair value of interest rate swaps, net of taxes	1,085	1,308
Comprehensive income	67,102	45,200
Statements of cash flows
Cash (used in) provided by operating activities	(40,089)	39,641
Dividends paid	(21,313)	(193,956)
Cash used in financing activities	(21,445)	(130,077)
Parent Company
Current Assets
Intercompany	19,202		34,549
Other current assets	19,254		19,033
Total current assets	57,607		134,938
Other assets	56,313		61,218
Intercompany	2,487,880		2,480,760
Investments in subsidiaries	2,253,491		2,180,814
Total assets	4,944,291		4,946,342
Current liabilities:
Total current liabilities	23,442		38,407
Intercompany	1,057,660		1,091,982
Deferred income taxes	10,322		14,151
Total liabilities	3,272,043		3,321,503
Stockholder's equity:
Capital in excess of par	1,558,546		1,556,926
Retained earnings	114,005		81,497
Accumulated other comprehensive income (loss)	(303)		(13,584)
Total stockholder's equity	1,672,248		1,624,839
Total liabilities and stockholder's equity	4,944,291		4,946,342
Statements of income and comprehensive income
Intercompany interest	39,708	39,658
Total other income (expense)	5,820	2,599
Income before income taxes	(16,453)	(20,238)
Provision for income taxes	(5,369)	(6,128)
Equity in income of subsidiaries	64,905	59,281
Net Income	53,821	45,171
Change in fair value of interest rate swaps, net of taxes	1,085	1,308
Comprehensive income	67,102	45,200
Statements of cash flows
Cash (used in) provided by operating activities	(6,378)	82,020
Dividends paid	(21,313)	(193,956)
Intercompany	(33,387)	(23,111)
Cash used in financing activities	(54,700)	(153,188)
Parent Company | As Reported
Current Assets
Intercompany			857,700
Total current assets			939,000
Intercompany			323,300
Investments in subsidiaries			3,211,100
Total assets			4,562,000
Current liabilities:
Total current liabilities			38,400
Deferred income taxes			721,800
Total liabilities			2,937,200
Stockholder's equity:
Capital in excess of par			1,556,900
Retained earnings			81,500
Accumulated other comprehensive income (loss)			(13,600)
Total stockholder's equity			1,624,800
Total liabilities and stockholder's equity			4,562,000
Statements of income and comprehensive income
Intercompany interest		2,500
Total other income (expense)		(34,500)
Income before income taxes		(57,400)
Provision for income taxes		(17,900)
Equity in income of subsidiaries		84,700
Net Income		45,200
Change in fair value of interest rate swaps, net of taxes		1,300
Comprehensive income		45,200
Statements of cash flows
Cash (used in) provided by operating activities		58,900
Dividends paid		(194,000)
Cash used in financing activities		(130,100)
Guarantor Subsidiaries
Current Assets
Other current assets	22,461		24,104
Total current assets	864,034		771,635
Other assets	5,909		6,937
Intercompany	1,015,578		1,062,900
Total assets	4,602,387		4,565,976
Current liabilities:
Intercompany	19,202		34,549
Total current liabilities	343,975		340,126
Intercompany	2,157,500		2,157,500
Deferred income taxes	637,726		637,726
Total liabilities	3,154,589		3,150,002
Stockholder's equity:
Capital in excess of par	1,211,581		1,211,581
Retained earnings	239,034		208,295
Accumulated other comprehensive income (loss)	(2,817)		(3,902)
Total stockholder's equity	1,447,798		1,415,974
Total liabilities and stockholder's equity	4,602,387		4,565,976
Statements of income and comprehensive income
Intercompany interest	(34,798)	(37,133)
Total other income (expense)	(33,847)	(35,036)
Income before income taxes	49,357	47,462
Provision for income taxes	18,615	17,857
Net Income	30,742	29,605
Change in fair value of interest rate swaps, net of taxes	1,085	1,308
Comprehensive income	31,827	30,913
Statements of cash flows
Cash (used in) provided by operating activities	(54,362)	(17,526)
Intercompany	33,387	23,111
Cash used in financing activities	33,387	23,111
Guarantor Subsidiaries | As Reported
Current Assets
Other current assets			43,100
Total current assets			790,700
Other assets			68,200
Total assets			3,583,300
Current liabilities:
Intercompany			1,121,800
Total current liabilities			1,424,300
Deferred income taxes			22,000
Total liabilities			1,464,000
Stockholder's equity:
Capital in excess of par			352,000
Retained earnings			1,767,300
Total stockholder's equity			2,119,300
Total liabilities and stockholder's equity			3,583,300
Statements of income and comprehensive income
Total other income (expense)		2,100
Income before income taxes		84,600
Provision for income taxes		29,600
Net Income		55,000
Comprehensive income		55,000
Statements of cash flows
Cash (used in) provided by operating activities		5,600
Non-Guarantor Subsidiaries
Current Assets
Other current assets	34,382		35,442
Total current assets	355,747		340,375
Other assets	78		79
Intercompany	42,082		29,082
Total assets	1,394,259		1,349,103
Current liabilities:
Total current liabilities	131,708		135,218
Intercompany	330,380		323,260
Deferred income taxes	99,583		99,542
Total liabilities	588,566		584,263
Stockholder's equity:
Capital in excess of par	733,411		733,411
Retained earnings	61,136		30,198
Accumulated other comprehensive income (loss)	11,146		1,231
Total stockholder's equity	805,693		764,840
Total liabilities and stockholder's equity	1,394,259		1,349,103
Statements of income and comprehensive income
Intercompany interest	(4,910)	(2,525)
Total other income (expense)	(5,801)	(4,248)
Income before income taxes	47,449	41,216
Provision for income taxes	13,286	11,540
Net Income	34,163	29,676
Comprehensive income	44,078	32,479
Statements of cash flows
Cash (used in) provided by operating activities	23,876	(11,991)
Dividends paid	(3,225)	(12,862)
Cash used in financing activities	(3,357)	(12,862)
Non-Guarantor Subsidiaries | As Reported
Current Assets
Intercompany			264,100
Other current assets			35,400
Total current assets			604,400
Other assets			100
Total assets			1,584,100
Current liabilities:
Total current liabilities			135,200
Intercompany			323,300
Deferred income taxes			7,500
Total liabilities			492,300
Stockholder's equity:
Capital in excess of par			301,300
Retained earnings			789,300
Accumulated other comprehensive income (loss)			1,200
Total stockholder's equity			1,091,800
Total liabilities and stockholder's equity			1,584,100
Statements of income and comprehensive income
Intercompany interest		(2,500)
Total other income (expense)		(4,200)
Income before income taxes		41,200
Provision for income taxes		11,500
Net Income		29,700
Comprehensive income		29,700
Statements of cash flows
Cash (used in) provided by operating activities		(24,900)
Eliminations
Current Assets
Intercompany	(19,202)		(34,549)
Total current assets	(19,202)		(34,549)
Intercompany	(3,545,540)		(3,572,742)
Investments in subsidiaries	(2,253,491)		(2,180,814)
Total assets	(5,818,233)		(5,788,105)
Current liabilities:
Intercompany	(19,202)		(34,549)
Total current liabilities	(19,202)		(34,549)
Intercompany	(3,545,540)		(3,572,742)
Total liabilities	(3,564,742)		(3,607,291)
Stockholder's equity:
Capital in excess of par	(1,944,992)		(1,944,992)
Retained earnings	(300,170)		(238,493)
Accumulated other comprehensive income (loss)	(8,329)		2,671
Total stockholder's equity	(2,253,491)		(2,180,814)
Total liabilities and stockholder's equity	(5,818,233)		(5,788,105)
Statements of income and comprehensive income
Equity in income of subsidiaries	(64,905)	(59,281)
Net Income	(64,905)	(59,281)
Change in fair value of interest rate swaps, net of taxes	(1,085)	(1,308)
Comprehensive income	(75,905)	(63,392)
Statements of cash flows
Cash (used in) provided by operating activities	(3,225)	(12,862)
Dividends paid	3,225	12,862
Cash used in financing activities	3,225	12,862
Eliminations | As Reported
Current Assets
Intercompany			(1,121,800)
Total current assets			(1,121,800)
Intercompany			(323,300)
Investments in subsidiaries			(3,211,100)
Total assets			(4,656,100)
Current liabilities:
Intercompany			(1,121,800)
Total current liabilities			(1,121,800)
Intercompany			(323,300)
Total liabilities			(1,445,000)
Stockholder's equity:
Capital in excess of par			(653,300)
Retained earnings			(2,556,600)
Accumulated other comprehensive income (loss)			(1,200)
Total stockholder's equity			(3,211,100)
Total liabilities and stockholder's equity			(4,656,100)
Statements of income and comprehensive income
Equity in income of subsidiaries		(84,700)
Net Income		(84,700)
Comprehensive income		$ (84,700)