Condensed Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	AOCI Attributable to Parent [Member]	Noncontrolling Interest [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Oct. 31, 2017	$ 4,537,090	$ 1,779	$ 720,115	$ 4,474,064	$ (662,854)	$ (1,910)	$ 5,896
Net income	243,917			243,917
Purchase of treasury stock	(291,478)				(291,478)
Exercise of stock options and stock based compensation issuances	8,536		(19,984)		28,520
Employee stock purchase plan issuances	593		98		495
Stock-based compensation	15,346		15,346
Dividends declared	(29,211)			(29,211)
Other comprehensive income	341					341
Net Income (Loss) Attributable to Noncontrolling Interest	(3)						(3)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Apr. 30, 2018	4,486,596	1,779	715,949	4,690,272	(925,317)	(1,980)	5,893
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Jan. 31, 2018	4,464,890	1,779	709,800	4,595,233	(845,668)	(2,150)	5,896
Net income	111,810			111,810
Purchase of treasury stock	(81,508)				(81,508)
Exercise of stock options and stock based compensation issuances	1,236		(347)		1,583
Employee stock purchase plan issuances	315		39		276
Stock-based compensation	6,457		6,457
Dividends declared	(16,771)			(16,771)
Other comprehensive income	170					170
Net Income (Loss) Attributable to Noncontrolling Interest	(3)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Apr. 30, 2018	4,486,596	1,779	715,949	4,690,272	(925,317)	(1,980)	5,893
Cumulative effect adjustment upon adoption of new accounting pronouncements	1,465		374	1,502		(411)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Oct. 31, 2018	4,768,912	1,779	727,053	5,161,551	(1,130,878)	694	8,713
Net income	241,374			241,374
Purchase of treasury stock	(25,244)				(25,244)
Exercise of stock options and stock based compensation issuances	578		(19,667)		20,245
Employee stock purchase plan issuances	720		9		711
Stock-based compensation	13,916		13,916
Dividends declared	(32,514)			(32,514)
Other comprehensive income	112					112
Net Income (Loss) Attributable to Noncontrolling Interest	(4)						(4)
Capital contributions	36,377						36,377
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Apr. 30, 2019	4,986,240	1,779	721,311	5,352,424	(1,135,166)	806	45,086
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Jan. 31, 2019	4,861,189	1,779	717,405	5,239,251	(1,139,623)	750	41,627
Net income	129,324			129,324
Purchase of treasury stock	(101)				(101)
Exercise of stock options and stock based compensation issuances	2,728		(1,473)		4,201
Employee stock purchase plan issuances	405		48		357
Stock-based compensation	5,331		5,331
Dividends declared	(16,151)			(16,151)
Other comprehensive income	56					56
Net Income (Loss) Attributable to Noncontrolling Interest	(4)						(4)
Capital contributions	3,463						3,463
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Apr. 30, 2019	4,986,240	1,779	721,311	5,352,424	(1,135,166)	806	45,086
Cumulative effect adjustment upon adoption of new accounting pronouncements	$ (17,987)			$ (17,987)

Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation.

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