Aggregate non discounted lease payments over twenty year term.

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Area of land and buildings under lease.

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Claim period.

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Lease agreement period.

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Line of credit facility covenant compliance amount.

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Number of credit facilities.

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Potential to expand credit facility under credit agreement.

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Undiscounted annual lease payments.

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Fair value portion of the lessor's net investment in nonoperating or leveraged leases expected to be realized or consumed after one year or normal operating cycle, if longer.

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The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

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The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

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

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

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

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For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

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Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The effective interest rate at the end of the reporting period.

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The effective interest rate during the reporting period.

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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.

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Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Debt - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	0 Months Ended			12 Months Ended
	Aug. 29, 2014 Facilities	Oct. 01, 2011	Jun. 01, 2004 sqft	Dec. 31, 2014	Dec. 31, 2013	Oct. 01, 2011 sqft
Credit Facilities [Line Items]
Number of credit facilities	2nnbr_NumberOfCreditFacilities
Net capitalized loan origination costs				$ 1,398
Proceeds from long-term debt	344,750			344,750
Debt discount (premium)	5,250
Interest rate				0.00%
Total debt				350,186us-gaap_LongTermDebt	36,477us-gaap_LongTermDebt
Current Maturities of Long-Term debt				(22,160)us-gaap_LongTermDebtCurrent	(10,477)us-gaap_LongTermDebtCurrent
Long-term debt excluding current maturities of long-term debt				(328,026)us-gaap_LongTermDebtNoncurrent	(26,000)us-gaap_LongTermDebtNoncurrent
Period of lease agreement		20 years	20 years
Lease of land and building		75,000nnbr_AreaOfLandAndBuildingsUnderLease	110,000nnbr_AreaOfLandAndBuildingsUnderLease			75,000nnbr_AreaOfLandAndBuildingsUnderLease
Undiscounted annual lease payments		193nnbr_UndiscountedAnnualLeasePayments	299nnbr_UndiscountedAnnualLeasePayments
Aggregate non discounted lease payments over the twenty year term		3,850	5,988
Capital leased assets reflected in property, plant and equipment, net				24,997
accumulated depreciation of capital leased assets				618
Land Owned [Member]
Credit Facilities [Line Items]
Fair value		892	545			892
Building [Member]
Credit Facilities [Line Items]
Fair value		1,156	2,016			1,156
4.64% Fixed Rate Notes [Member]
Credit Facilities [Line Items]
Borrowings	20,000			20,000
Net capitalized loan origination costs	30
French Safeguard [Member]
Credit Facilities [Line Items]
Total debt				2,560
Current Maturities of Long-Term debt				(330)
Long-term debt excluding current maturities of long-term debt				(2,230)
Chinese [Member]
Credit Facilities [Line Items]
Interest rate				4.95%
Term Loan B [Member]
Credit Facilities [Line Items]
Borrowings	350,000			340,005
Borrowings				350,000
Maturity period				7 years
Repayment of term loan, percentage				5.00%
Potential to expand credit facility under credit agreement				50,000
Unamortized balance				7,945
Interest rate				0.2318%
ABL Revolver [Member]
Credit Facilities [Line Items]
Borrowings	100,000			100,000
Maturity period				5 years
Potential to expand credit facility under credit agreement				50,000
Unamortized balance				968
ABL borrowing				8,000
Interest rate				0.1565%
Revolving Credit Facility [Member]
Credit Facilities [Line Items]
Borrowings				100,000
Net capitalized loan origination costs	$ 1,368
Minimum [Member] \| French Safeguard [Member]
Credit Facilities [Line Items]
Creditor's claim period				10 years
Minimum [Member] \| Brazilian [Member]
Credit Facilities [Line Items]
Lines of credit interest rate				10.50%
Maximum [Member] \| Brazilian [Member]
Credit Facilities [Line Items]
Lines of credit interest rate				21.80%