Cover - USD ($)		12 Months Ended
	Dec. 31, 2020	Dec. 31, 2020	Feb. 08, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type		10-K/A
Amendment Flag		false
Document Annual Report	true
Document Transition Report		false
Document Period End Date		Dec. 31, 2020
Document Fiscal Period Focus		FY
Document Fiscal Year Focus		2020
Current Fiscal Year End Date		--12-31
Entity File Number		1-12691
Entity Registrant Name		ION Geophysical Corporation
Entity Central Index Key		0000866609
Entity Tax Identification Number		22-2286646
Entity Incorporation, State or Country Code		DE
Entity Address, Address Line One		2105 CityWest Blvd
Entity Address, Address Line Two		Suite 100
Entity Address, City or Town		Houston
Entity Address, State or Province		TX
Entity Address, Postal Zip Code		77042-2855
City Area Code		281
Local Phone Number		933-3339
Title of 12(b) Security		Common Stock, $0.01 par value
Trading Symbol		IO
Security Exchange Name		NYSE
Entity Well-known Seasoned Issuer		No
Entity Voluntary Filers		No
Entity Current Reporting Status		Yes
Entity Interactive Data Current		Yes
Entity Filer Category		Non-accelerated Filer
Entity Small Business		false
Entity Emerging Growth Company		false
Entity Shell Company		false
Entity Public Float				$ 26,800,000
Entity Common Stock, Shares Outstanding			28,811,207
ICFR Auditor Attestation Flag		true