Lease Obligations - Maturities of Lease Obligations (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Operating Leases (a)
2021	$ 8,047
2022	9,011
2023	9,826
2024	7,096
2025	9,190
Thereafter	20,036
Total lease payments	63,206
Less: imputed interest	(14,441)
Total	48,765
Finance Leases
2021	1,254
2022	130
2023	0
2024	0
2025	0
Thereafter	0
Total lease payments	1,384
Less: imputed interest	(69)
Total	1,315	$ 1,869
Total
2021	9,301
2022	9,141
2023	9,826
2024	7,096
2025	9,190
Thereafter	20,036
Total lease payments	64,590
Less: imputed interest	(14,510)
Total	$ 50,080

Lease Liabilities, Payments Due [Abstract]

No definition available.

Name:	io_LeaseLiabilitiesPaymentsDueAbstract
Namespace Prefix:	io_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Lease, Liability

+ References

No definition available.

+ Details

Name:	io_LeaseLiability
Namespace Prefix:	io_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Lease, Liability, Payments, Due

+ References

No definition available.

+ Details

Name:	io_LeaseLiabilityPaymentsDue
Namespace Prefix:	io_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Lease, Liability, Payments, Due in Next Rolling Twelve Months

+ References

No definition available.

+ Details

Name:	io_LeaseLiabilityPaymentsDueinNextRollingTwelveMonths
Namespace Prefix:	io_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Lease, Liability, Payments, Due in Rolling After Year Five

+ References

No definition available.

+ Details

Name:	io_LeaseLiabilityPaymentsDueinRollingAfterYearFive
Namespace Prefix:	io_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Lease, Liability, Payments, Due in Rolling Year Five

+ References

No definition available.

+ Details

Name:	io_LeaseLiabilityPaymentsDueinRollingYearFive
Namespace Prefix:	io_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Lease, Liability, Payments, Due in Rolling Year Four

+ References

No definition available.

+ Details

Name:	io_LeaseLiabilityPaymentsDueinRollingYearFour
Namespace Prefix:	io_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Lease, Liability, Payments, Due in Rolling Year Three

+ References

No definition available.

+ Details

Name:	io_LeaseLiabilityPaymentsDueinRollingYearThree
Namespace Prefix:	io_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Lease, Liability, Payments, Due in Rolling Year Two

+ References

No definition available.

+ Details

Name:	io_LeaseLiabilityPaymentsDueinRollingYearTwo
Namespace Prefix:	io_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Lease, Liability, Undiscounted Excess Amount

+ References

No definition available.

+ Details

Name:	io_LeaseLiabilityUndiscountedExcessAmount
Namespace Prefix:	io_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_FinanceLeaseLiabilitiesPaymentsDueAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

+ Details

Name:	us-gaap_FinanceLeaseLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease.

+ References

+ Details

Name:	us-gaap_FinanceLeaseLiabilityPaymentsDue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease, due after fifth fiscal year following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

+ Details

Name:	us-gaap_FinanceLeaseLiabilityPaymentsDueInNextRollingTwelveMonths
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease, due after fifth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

Name:	us-gaap_FinanceLeaseLiabilityPaymentsDueInRollingAfterYearFive
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease, due in fifth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

Name:	us-gaap_FinanceLeaseLiabilityPaymentsDueInRollingYearFive
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease, due in fourth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

Name:	us-gaap_FinanceLeaseLiabilityPaymentsDueInRollingYearFour
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease, due in third rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

Name:	us-gaap_FinanceLeaseLiabilityPaymentsDueInRollingYearThree
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease, due in second rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

Name:	us-gaap_FinanceLeaseLiabilityPaymentsDueInRollingYearTwo
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

+ References

+ Details

Name:	us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease.

+ References

+ Details

Name:	us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

Name:	us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterRollingYearFive
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

+ References

+ Details

Name:	us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueInRollingYearFive
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

+ References

+ Details

Name:	us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueInRollingYearFour
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

+ References

+ Details

Name:	us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueInRollingYearThree
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

+ References

+ Details

Name:	us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueInRollingYearTwo
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease, due in next rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

+ References

+ Details

Name:	us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextRollingTwelveMonths
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

+ References

+ Details

Name:	us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

+ Details

Name:	us-gaap_OperatingLeaseLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant