Debt instrument applicable margin rate.

No definition available.

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- Definition

Debt instrument covenant leverage ratio.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Debt instrument percentage of excess cash flow to be used for mandatory prepayment starting next fiscal year.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Debt Instrument, Percentage Of Excess Cash Flow To Be Used For Mandatory Prepayment, Step-Down Percentage

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Debt instrument percentage of net cash proceeds from issuances of permitted equity securities to be used for mandatory prepayment.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Debt instrument percentage of net cash proceeds from issuances or incurrence of additional debt to be used for mandatory prepayment.

+ References

No definition available.

+ Details

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Namespace Prefix:	neo_
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Balance Type:	na
Period Type:	instant

- Definition

Debt instrument percentage of net cash proceeds from sales and dispositions subject to certain reinvestment rights.

+ References

No definition available.

+ Details

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Namespace Prefix:	neo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line Of Credit Facility, Annual Principal Amortization, After Year Four

+ References

No definition available.

+ Details

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Namespace Prefix:	neo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line Of Credit Facility, Annual Principal Amortization, Year Four

+ References

No definition available.

+ Details

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Namespace Prefix:	neo_
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Period Type:	duration

- Definition

Line Of Credit Facility, Annual Principal Amortization, Year One

+ References

No definition available.

+ Details

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Namespace Prefix:	neo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line Of Credit Facility, Annual Principal Amortization, Year Three

+ References

No definition available.

+ Details

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Namespace Prefix:	neo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line Of Credit Facility, Annual Principal Amortization, Year Two

+ References

No definition available.

+ Details

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Namespace Prefix:	neo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of credit facility swingline sublimit.

+ References

No definition available.

+ Details

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Namespace Prefix:	neo_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtWeightedAverageInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
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-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	duration

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=99376301&loc=d3e1336-112600

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=99376301&loc=d3e1314-112600

+ Details

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

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Balance Type:
Period Type:

- Details

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Period Type:

- Details

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- Details

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- Details

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Period Type:

- Details

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- Details

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Debt - Narrative (Detail) - USD ($)		3 Months Ended			9 Months Ended
Debt - Narrative (Detail) - USD ($)	Jun. 27, 2019	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jun. 21, 2018	Dec. 22, 2016
Line of Credit Facility [Line Items]
Long-term outstanding borrowings		$ 0	$ 5,000,000		$ 0
Debt issuance costs		723,000	$ 997,000		723,000
Loss on extinguishment of debt		$ 0		$ 0	$ (1,018,000)	$ 0
Debt instrument, weighted average interest rates		4.67%	4.56%		4.67%
Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility maximum borrowing capacity								$ 75,000,000.0
Line of credit facility, swingline sublimit								10,000,000.0
Proceeds from issuance of debt			$ 5,000,000.0
Term Loan
Line of Credit Facility [Line Items]
Long-term outstanding borrowings			87,900,000
Debt instrument, percentage of net cash proceeds from sales and dispositions subject to certain reinvestment rights		100.00%			100.00%
Debt instrument, percentage of net cash proceeds from issuances or incurrence of additional debt to be used for mandatory prepayment		100.00%			100.00%
Debt Instrument, maximum borrowing capacity							$ 30,000,000.0	$ 75,000,000.0
Debt instrument, percentage of excess cash flow to be used for mandatory prepayment starting next fiscal year		75.00%			75.00%
Debt instrument covenant leverage ratio					325.00%
Debt instrument, step-down percentage		50.00%			50.00%
Debt instrument, percentage of net cash proceeds from issuances of permitted equity securities to be used for mandatory prepayment		100.00%			100.00%
Term Loan \| Minimum
Line of Credit Facility [Line Items]
Debt instrument covenant leverage ratio					275.00%
Term Loan \| Maximum
Line of Credit Facility [Line Items]
Debt instrument covenant leverage ratio					325.00%
Term Loan \| Federal Funds Rate
Line of Credit Facility [Line Items]
Debt instrument variable interest rate					0.50%
Term Loan \| LIBOR
Line of Credit Facility [Line Items]
Debt instrument variable interest rate					1.00%
Term Loan \| LIBOR \| Minimum
Line of Credit Facility [Line Items]
Debt instrument applicable margin					2.25%
Term Loan \| LIBOR \| Maximum
Line of Credit Facility [Line Items]
Debt instrument applicable margin					4.00%
Term Loan \| Base Rate \| Minimum
Line of Credit Facility [Line Items]
Debt instrument applicable margin					1.25%
Term Loan \| Base Rate \| Maximum
Line of Credit Facility [Line Items]
Debt instrument applicable margin					3.00%
New Credit Agreement \| Federal Funds Rate
Line of Credit Facility [Line Items]
Debt instrument variable interest rate					0.50%
New Credit Agreement \| LIBOR
Line of Credit Facility [Line Items]
Debt instrument variable interest rate					1.00%
New Credit Agreement \| LIBOR \| Minimum
Line of Credit Facility [Line Items]
Debt instrument applicable margin					1.25%
New Credit Agreement \| LIBOR \| Maximum
Line of Credit Facility [Line Items]
Debt instrument applicable margin					2.25%
New Credit Agreement \| Base Rate \| Minimum
Line of Credit Facility [Line Items]
Debt instrument applicable margin					0.25%
New Credit Agreement \| Base Rate \| Maximum
Line of Credit Facility [Line Items]
Debt instrument applicable margin					1.25%
New Credit Agreement \| Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility maximum borrowing capacity	$ 100,000,000.0
Line of credit facility, swingline sublimit	$ 10,000,000.0
Commitment fee (as a percent)	0.25%
New Credit Agreement \| Revolving Credit Facility \| Minimum
Line of Credit Facility [Line Items]
Commitment fee (as a percent)	0.15%
New Credit Agreement \| Revolving Credit Facility \| Maximum
Line of Credit Facility [Line Items]
Commitment fee (as a percent)	0.35%
New Credit Agreement \| Term Loan
Line of Credit Facility [Line Items]
Line of credit facility maximum borrowing capacity	$ 100,000,000.0
Annual principal amortization, year one (as a percent)	5.00%
Annual principal amortization, year two (as a percent)	5.00%
Annual principal amortization, year three (as a percent)	7.50%
Annual principal amortization, year four (as a percent)	7.50%
Annual principal amortization, thereafter (as a percent)	10.00%
Line of credit facility, outstanding borrowings		$ 6,300,000			$ 6,300,000
Long-term outstanding borrowings		93,700,000			93,700,000
Debt issuance costs		$ 700,000			$ 700,000
Debt instrument, percentage of net cash proceeds from sales and dispositions subject to certain reinvestment rights		100.00%			100.00%
Debt instrument, percentage of net cash proceeds from issuances or incurrence of additional debt to be used for mandatory prepayment		100.00%			100.00%
New Credit Agreement \| Delayed Draw Term Loan
Line of Credit Facility [Line Items]
Line of credit facility maximum borrowing capacity	$ 50,000,000.0
Prior Financing Agreement
Line of Credit Facility [Line Items]
Loss on extinguishment of debt		$ 1,000,000.0
Prior Financing Agreement \| Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility, outstanding borrowings			5,000,000.0
Prior Financing Agreement \| Term Loan
Line of Credit Facility [Line Items]
Line of credit facility, outstanding borrowings			$ 7,900,000