Stock Options, Stock Purchase Plan and Warrants - Summarizes Information About Our Options Outstanding (Detail) (USD $)	12 Months Ended
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding number of options	4,012,096
Weighted average remaining contractual life outstanding	2 years 3 months 18 days
Outstanding average exercise price	$ 2.04
Weighted average remaining contractual life exercisable	1 year 7 months 6 days
Exercisable, number of options	2,379,378
Exercisable, average exercise Price	$ 1.27
Range One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price Range, Minimum	$ 0.00
Price Range, Maximum	$ 0.5
Outstanding number of options	105,000
Weighted average remaining contractual life outstanding	1 year 3 months 18 days
Outstanding average exercise price	$ 0.49
Weighted average remaining contractual life exercisable	1 year 3 months 18 days
Exercisable, number of options	105,000
Exercisable, average exercise Price	$ 0.49
Range Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price Range, Minimum	$ 0.51
Price Range, Maximum	$ 1.0
Outstanding number of options	1,007,000
Weighted average remaining contractual life outstanding	1 year 2 months 12 days
Outstanding average exercise price	$ 0.80
Weighted average remaining contractual life exercisable	1 year 2 months 12 days
Exercisable, number of options	1,007,000
Exercisable, average exercise Price	$ 0.80
Range Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price Range, Minimum	$ 1.01
Price Range, Maximum	$ 1.5
Outstanding number of options	833,096
Weighted average remaining contractual life outstanding	1 year 6 months
Outstanding average exercise price	$ 1.40
Weighted average remaining contractual life exercisable	1 year 6 months
Exercisable, number of options	671,596
Exercisable, average exercise Price	$ 1.39
Range Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price Range, Minimum	$ 1.51
Price Range, Maximum	$ 3.0
Outstanding number of options	973,000
Weighted average remaining contractual life outstanding	2 years 2 months 12 days
Outstanding average exercise price	$ 1.74
Weighted average remaining contractual life exercisable	2 years 2 months 12 days
Exercisable, number of options	499,041
Exercisable, average exercise Price	$ 1.73
Range Five [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price Range, Minimum	$ 3.01
Price Range, Maximum	$ 4.0
Outstanding number of options	674,500
Weighted average remaining contractual life outstanding	3 years 9 months 18 days
Outstanding average exercise price	$ 3.66
Weighted average remaining contractual life exercisable	3 years 4 months 24 days
Exercisable, number of options	96,741
Exercisable, average exercise Price	$ 3.80
Range Six [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price Range, Minimum	$ 4.01
Price Range, Maximum	$ 5.0
Outstanding number of options	379,500
Weighted average remaining contractual life outstanding	4 years 9 months 18 days
Outstanding average exercise price	$ 4.72
Weighted average remaining contractual life exercisable	0 years
Range Seven [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price Range, Minimum	$ 5.01
Price Range, Maximum	$ 6.0
Outstanding number of options	40,000
Weighted average remaining contractual life outstanding	4 years 8 months 12 days
Outstanding average exercise price	$ 5.44
Weighted average remaining contractual life exercisable	0 years

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

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice1
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageRemainingContractualTerm2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageRemainingContractualTerm2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_RangeAxis=neo_RangeFiveMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=neo_RangeFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=neo_RangeOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=neo_RangeSevenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=neo_RangeSixMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=neo_RangeThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=neo_RangeTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: