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The pro forma amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest as if the business combination or combinations had been completed at the beginning of a period.

No definition available.

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The pro forma amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations as if the business combination or combinations had been completed at the beginning of a period.

No definition available.

Name:	fnrn_BusinessAcquisitionsProFormaIncomeTaxExpenseBenefit
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The pro forma net amount of operating interest income (expense) as if the business combination or combinations had been completed at the beginning of a period.

No definition available.

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The pro forma amount of all noninterest expense as if the business combination or combinations had been completed at the beginning of a period.

No definition available.

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The pro forma amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified as if the business combination or combinations had been completed at the beginning of a period.

No definition available.

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Amount of deposits assumed at the acquisition date.

No definition available.

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Amount due from financing receivables acquired at the acquisition date.

No definition available.

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Amount of other liabilities, assumed at the acquisition date.

No definition available.

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Amount at cost basis, recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

No definition available.

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Amount of other assets acquired at the acquisition date.

No definition available.

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amount of expense recognized in the current period that reflects the allocation of capitalized costs associated with acquisition of business. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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No definition available.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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In a business combination in which the amount of net identifiable assets acquired and liabilities assumed exceeds the aggregate consideration transferred or to be transferred (as defined), this element represents the amount of gain recognized by the entity.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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No definition available.

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No definition available.

Name:	us-gaap_BusinessCombinationDescriptionAbstract
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Amount of assets acquired at the acquisition date.

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No definition available.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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No definition available.

Name:	us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract
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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

Name:	us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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The amount of property, plant, and equipment recognized as of the acquisition date.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The number of businesses acquired by the entity during the period.

No definition available.

Name:	us-gaap_NumberOfBusinessesAcquired
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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-Topic 805
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