Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Taxes [Line Items]
Number of subsequent years we may not able to qualify as REIT if failed to qualify for taxation as a REIT in any taxable year	4 years
Valuation allowance	$ 10	$ 18
Net increase or decrease in valuation allowance	(8)
Total deferred tax assets, net of valuation allowance	217	222
Cash paid for income taxes, net of refunds received	11	12
Proceeds from income tax refunds			$ 19
Unrecognized tax benefits	$ 1	1
Statutory federal income tax rate	21.00%
Recognized material interest or penalties	$ 0	$ 0	$ 0
Foreign Tax Jurisdiction \| Net Operating Loss and Capital Loss Carryover
Income Taxes [Line Items]
Valuation allowance as a percentage	100.00%
Valuation allowance	$ 5
U.S. Federal \| AOCI Foreign Exchange Net Loss
Income Taxes [Line Items]
Valuation allowance	$ 5
Lower Limit
Income Taxes [Line Items]
Percentage of annual taxable income Host Inc is required to distribute	90.00%

Deferred Tax Asset, Valuation Allowance, Percentage

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Income taxes.

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Percentage of taxable income required to be distributed.

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Subsequent Period Not Able To Qualify If Failed To Qualify As Real Estate Investment Trust In Any Taxable Year.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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

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The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

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Amount, after refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax.

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Amount of income tax refund received from tax jurisdiction.

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