Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2016
Deferred tax assets:
Reserves and accrued liabilities	$ 54,183	$ 40,959
Depreciation and amortization	455,007	353,838
NOL and credit carry forward	302,325	483,495
Other	39,405	9,397
Gross deferred tax assets	850,920	887,689
Valuation allowance	(135,978)	(142,650)	$ (185,898)	$ (1,489,780)
Deferred tax asset, net of valuation allowance	$ 714,942	$ 745,039