XML 59 R48.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Purchased Receivables - Allowance on Net Purchase Receivables (Details) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Purchased Receivable Allowance for Loan Loss Reserve [Roll Forward] |  |  |  |
Balance at beginning of period | $ 194,000 | $ 163,000 | $ 171,000 | $ 181,000
Charge-offs | (1,203,000) | (22,000) | (1,689,000) | (891,000)
Balance at end of period | 200,000 | 163,000 | 200,000 | 163,000
Purchased Receivable |  |  |  |
Purchased Receivable Allowance for Loan Loss Reserve [Roll Forward] |  |  |  |
Charge-offs | 0 | 0 | 0 | 0
Recoveries | 0 | 0 | 0 | 0
Charge-offs net of recoveries | 0 | 0 | 0 | 0
Reserve for (recovery from) purchased receivables | $ 6,000 | $ 0 | $ 29,000 | $ (18,000)

X
- Definition Purchased Receivable Allowance for Loan Loss Reserve [Roll Forward] + References No definition available. + Details
Name: | nrim_PurchasedReceivableAllowanceforLoanLossReserveRollForward
Namespace Prefix: | nrim_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Reserve For Purchased Receivable Gains Losses + References No definition available. + Details
Name: | nrim_ReserveForPurchasedReceivableGainsLosses
Namespace Prefix: | nrim_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of increase (decrease) in the allowance for doubtful accounts. + References No definition available. + Details
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of recoveries of receivables doubtful of collection that were previously charged off. + References No definition available. + Details
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivableRecoveries
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of direct write-downs of financing receivables charged against the allowance. + 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 (c)(3) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130534-203044 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.5) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130543-203045 + Details
Name: | us-gaap_ProvisionForDoubtfulAccounts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=nrim_PurchasedReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |