XML 33 R30.htm IDEA: XBRL DOCUMENT
v3.2.0.727

Loans (Net Loans Held-for-Investment) (Details) - USD ($) $ in Thousands | 6 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013
Investments In Loans [Line Items] |  |  |  |  |  |
Document Period End Date | Jun. 30, 2015 |  |  |  |  |
Originated loans held-for-investment, net | $ 1,787,363 |  | $ 1,632,494 |  |  |
PCI Loans | 37,778 |  | 44,816 |  |  |
Loans acquired | 378,493 |  | 265,685 |  |  |
Loans held-for-investment, net | 2,203,634 |  | 1,942,995 |  |  |
Allowance for loan losses | (25,516) | $ (25,898) | (26,292) | $ (26,267) | $ (26,565) | $ (26,037)
Net loans held-for-investment | 2,178,118 |  | 1,916,703 |  |  |
Real Estate Loans |  |  |  |  |  |
Investments In Loans [Line Items] |  |  |  |  |  |
Loans receivable | 1,763,915 |  | 1,612,827 |  |  |
Commercial and industrial loans | 16,693 |  | 12,945 |  |  |
Other loans | 1,947 |  | 2,157 |  |  |
Total commercial and industrial and other loans | 18,640 |  | 15,102 |  |  |
Deferred loan cost, net | 4,808 |  | 4,565 |  |  |
Originated loans held-for-investment, net | 1,787,363 |  | 1,632,494 |  |  |
PCI Loans |  |  | 44,816 |  |  |
Real Estate Loans | Multifamily |  |  |  |  |  |
Investments In Loans [Line Items] |  |  |  |  |  |
Loans receivable | 1,218,702 |  | 1,072,193 |  |  |
Loans held-for-investment, net | 1,221,093 |  | 1,074,539 |  |  |
Allowance for loan losses | (13,208) | (12,698) | (12,219) | (9,880) | (9,814) | (9,374)
Real Estate Loans | Commercial real estate |  |  |  |  |  |
Investments In Loans [Line Items] |  |  |  |  |  |
Loans receivable | 391,235 |  | 390,288 |  |  |
Loans held-for-investment, net | 391,882 |  | 390,885 |  |  |
Allowance for loan losses | (7,341) | (8,483) | (9,309) | (11,882) | (12,359) | (12,619)
Real Estate Loans | One-to-four family residential mortgage |  |  |  |  |  |
Investments In Loans [Line Items] |  |  |  |  |  |
Loans receivable | 80,557 |  | 74,401 |  |  |
Loans held-for-investment, net | 81,177 |  | 74,990 |  |  |
Allowance for loan losses | (1,107) | (870) | (951) | (1,012) | (818) | (875)
Real Estate Loans | Home equity and lines of credit |  |  |  |  |  |
Investments In Loans [Line Items] |  |  |  |  |  |
Loans receivable | 57,518 |  | 54,533 |  |  |
Loans held-for-investment, net | 58,596 |  | 55,486 |  |  |
Allowance for loan losses | (941) | (842) | (901) | (993) | (958) | (860)
Real Estate Loans | Construction and land |  |  |  |  |  |
Investments In Loans [Line Items] |  |  |  |  |  |
Loans receivable | 15,903 |  | 21,412 |  |  |
Loans held-for-investment, net | 15,925 |  | 21,445 |  |  |
Allowance for loan losses | (185) | $ (218) | (266) | $ (156) | $ (227) | $ (205)
Loans acquired |  |  |  |  |  |
Investments In Loans [Line Items] |  |  |  |  |  |
Loans acquired | 378,493 |  | 265,685 |  |  |
Loans held-for-investment, net | 2,203,634 |  | 1,942,995 |  |  |
Allowance for loan losses | (25,516) |  | (26,292) |  |  |
Loans acquired | Multifamily |  |  |  |  |  |
Investments In Loans [Line Items] |  |  |  |  |  |
Loans acquired | 17,431 |  | 18,844 |  |  |
Loans acquired | Commercial real estate |  |  |  |  |  |
Investments In Loans [Line Items] |  |  |  |  |  |
Loans acquired | 11,401 |  | 11,999 |  |  |
Loans acquired | One-to-four family residential mortgage |  |  |  |  |  |
Investments In Loans [Line Items] |  |  |  |  |  |
Loans acquired | 349,661 |  | 234,478 |  |  |
Loans acquired | Construction and land |  |  |  |  |  |
Investments In Loans [Line Items] |  |  |  |  |  |
Loans acquired | $ 0 |  | $ 364 |  |  |

X
- Definition The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD. + References No definition available. + Details
Name: | dei_DocumentPeriodEndDate
Namespace Prefix: | dei_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Certain Loans Acquired In Transfer + References No definition available. + Details
Name: | nfbk_CertainLoansAcquiredInTransfer
Namespace Prefix: | nfbk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Deferred loan cost, net. + References No definition available. + Details
Name: | nfbk_DeferredLoanCostNet
Namespace Prefix: | nfbk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Investments In Loans [Line Items] + References No definition available. + Details
Name: | nfbk_InvestmentsInLoansLineItems
Namespace Prefix: | nfbk_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Loans receivable commercial and industrial insurance premium and other loans. + References No definition available. + Details
Name: | nfbk_LoansReceivableCommercialAndIndustrialInsurancePremiumAndOtherLoans
Namespace Prefix: | nfbk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Originated loans held-for-investment, net + References No definition available. + Details
Name: | nfbk_OriginatedLoansHeldForInvestmentNet
Namespace Prefix: | nfbk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Purchased credit-impaired (PCI) loans held-for-investment + References No definition available. + Details
Name: | nfbk_PurchasedCreditImpairedLoansHeldForInvestment
Namespace Prefix: | nfbk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 6 -Section L -Subsection 1 + Details
Name: | us-gaap_LoansAndLeasesReceivableAllowance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount before allowance of consumer real estate loans. Includes, but not limited to, construction financing, residential mortgage loans, and home equity lines of credit. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(a)(2),(3),(b)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522 + Details
Name: | us-gaap_LoansAndLeasesReceivableConsumerRealEstate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5074-111524 + Details
Name: | us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
Name: | us-gaap_LoansAndLeasesReceivableNetReportedAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount before allowance of other loans and leases not otherwise specified in the taxonomy. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
Name: | us-gaap_LoansAndLeasesReceivableOther
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount before allowance of loans issued to commercial and industrial institutions. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes real estate loans and loans covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(a)(1)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5066-111524 + Details
Name: | us-gaap_LoansReceivableCommercialAndIndustrial
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | nfbk_FinancingReceivableByInvestmentTypeAxis=nfbk_RealEstateLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_MultifamilyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=nfbk_OneToFourFamilyResidentialMortgageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_HomeEquityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=nfbk_ConstructionAndLandMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | nfbk_FinancingReceivableByInvestmentTypeAxis=nfbk_LoansAcquiredMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |