Taxes on Earnings (Details 2)	12 Months Ended
Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2017
Differences between the U.S. federal statutory income tax rate and HP's effective tax rate
U.S. federal statutory income tax rate	21.00%	23.30%	35.00%
State income taxes, net of federal tax benefit	(0.10%)	4.30%	3.00%
Lower rates in other jurisdictions, net	(7.30%)	(121.40%)	(426.30%)
Valuation allowance	5.80%	(59.80%)	310.00%
U.S. permanent differences	6.00%	39.30%	27.80%
Uncertain tax positions	(14.70%)	(694.80%)	(8.40%)
Impacts of the Tax Act	24.50%	158.00%	0.00%
Other, net	(2.70%)	0.40%	(1.40%)
Effective tax rate (as a percent)	32.50%	(650.70%)	(60.30%)

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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