Stockholders' Equity (Details) (USD $)	0 Months Ended				3 Months Ended								12 Months Ended			0 Months Ended		0 Months Ended			12 Months Ended
	Feb. 04, 2013	Jan. 29, 2013	Feb. 28, 2012	Jan. 05, 2012	Oct. 31, 2013	Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2013	Oct. 31, 2012	Jul. 31, 2012	Apr. 30, 2012	Jan. 31, 2012	Oct. 31, 2013	Oct. 31, 2012	Oct. 31, 2011	Feb. 04, 2013 Forward Sale Agreement [Member]	Jan. 29, 2013 Forward Sale Agreement [Member]	Feb. 22, 2013 Additional Forward Sale Agreement [Member]	Oct. 31, 2013 Additional Forward Sale Agreement [Member]	Jan. 29, 2013 Additional Forward Sale Agreement [Member] Maximum [Member]	Oct. 31, 2013 Reclassification Out Of Accumulated Other Comprehensive Income [Member]	Oct. 31, 2012 Reclassification Out Of Accumulated Other Comprehensive Income [Member]	Dec. 16, 2005 Common Stock Open Market Purchase Program [Member]	Sep. 30, 2004 Common Stock Open Market Purchase Program [Member]	Dec. 16, 2005 ASR Program [Member]	Mar. 06, 2009 Common Stock Open Market Purchase Program and ASR Program [Member]	Dec. 16, 2005 Common Stock Open Market Purchase Program and ASR Program [Member]	Oct. 31, 2013 Employee Stock Purchase Plan [Member]	Oct. 31, 2013 Dividend Reinvestment Plan [Member]	Oct. 31, 2013 Share Based Compensation Plans [Member]
Stockholders' Equity [Abstract]
Common Stock, Shares, Outstanding, Beginning Balance								72,250,000				72,318,000	72,250,000	72,318,000	72,282,000
Common Stock, Value, Issued, Beginning Balance								$ 442,461,000				$ 446,791,000	$ 442,461,000	$ 446,791,000	$ 445,640,000
Stock Issued During Period Shares Employee Stock Purchase Plans (ESPP)													33,000	30,000	30,000
Stock Issued During Period Value Employee Stock Purchase Plan (ESPP)													1,056,000	894,000	870,000
Stock Issued During Period Shares Dividend Reinvestment Plan (DRIP)													720,000	677,000	657,000
Stock Issued During Period Value Dividend Reinvestment Plan (DRIP)													22,791,000	20,508,000	18,834,000
Shares Issued During Period Shares Incentive Compensation Plan (ICP)													96,000	25,000	149,000
Shares Issued During Period Value Incentive Compensation Plan (ICP)													3,065,000	796,000	4,451,000
Shares Repurchased During Period Shares Accelerated Share Repurchase (ASR) Plan				(800,000)										(800,000)	(800,000)
Common Stock Repurchased														(26,528,000)	(23,004,000)
Issuance of commons stock shares through public share offering, net of underwriting fees	3,000,000												3,000,000
Issuance of common stock through public share offering, net of underwriting fees					92,640,000								92,640,000
Expenses From Issuance of Common Stock													(369,000)
Common Stock, Shares, Outstanding, Ending Balance					76,099,000				72,250,000				76,099,000	72,250,000	72,318,000
Common Stock, Value, Issued, Ending Balance					561,644,000				442,461,000				561,644,000	442,461,000	446,791,000
Accelerated Share Repurchases Initial Price Paid Per Share				$ 33.77
Stock Repurchased During Period Value At Initial Price ASR Plan				27,000,000
Accelerated Share Repurchases Settlement Payment Or Receipt			500,000
Accelerated Share Repurchases Weighted Average Purchase Price Per Share			$ 33.25
Accelerated Share Repurchases Discount On Weighted Average Purchase Price Per Share			$ 0.09
Accelerated Share Repurchases Final Price Paid Per Share			$ 33.16
Class of Stock [Line Items]
Common Stock Reserved For Future Issuance					2,798,000								2,798,000															210,000	1,538,000	1,050,000
Authorized Common Stock Repurchases Shares																							6,000,000	3,000,000			10,000,000
Additional Authorized Common Stock Repurchases Shares																									4,000,000	4,000,000
Accumulated Other Comprehensive Income Loss [Abstract]
Accumulated OCIL beginning balance, net of tax								(305,000)				(452,000)	(305,000)	(452,000)
Other comprehensive income (loss) before reclassifications, net of tax													(109,000)	(826,000)
Amounts reclassified, net of tax													130,000	973,000
Total other comprehensive income													21,000	147,000	78,000
Accumulated OCIL ending balance, net of tax					(284,000)				(305,000)				(284,000)	(305,000)	(452,000)
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income from Equity Method Investments													26,056,000	23,904,000	24,027,000						(215,000)	(1,594,000)
Other income (expense) income taxes													(8,612,000)	(9,116,000)	(8,218,000)						85,000	621,000
Net Income					(5,003,000)	(2,293,000)	55,790,000	85,923,000	(1,959,000)	(4,613,000)	50,192,000	76,227,000	134,417,000	119,847,000	113,568,000						(130,000)	(973,000)
Common Stock Underwriting Agreement [Line Items]
Maximum Number Of Shares To Be Purchased		4,600,000
Forward Contract Shares																	1,000,000			600,000
Equity Issuance, Date Direct Shares													Feb. 04, 2013
Common Stock Issued, Value	$ 92,600,000												$ 119,552,000	$ 22,198,000	$ 24,155,000
Common Stock Issued, Shares	3,000,000												3,000,000
Price Per Share Gross	$ 32
Underwriter Discount	$ 1.12
Net Settlement Price Per Share	$ 30.88																	$ 30.88
Forward Shares To Be Borrowed By Forward Counterparty																1,000,000		600,000
Option to Purchase Settlement Date																			Feb. 22, 2013
Shares Subject To Underwriters Option To Purchase																		600,000