Leases - Summary Of Supplemental Cash Flow And Other Information Related To Operating Leases (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Leases [Abstract]
Cash payments (receipts) included in the measurement of operating lease liabilities, net	$ 801	$ (2,323)

Cash payments (proceeds) included in measurement of operating lease liabilities.

No definition available.

Name:	ionq_CashPaymentsProceedsIncludedInMeasurementOfOperatingLeaseLiabilities
Namespace Prefix:	ionq_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration