S000107710 [Member] Performance Management - NORTHERN TRUST CALIFORNIA TAX-EXEMPT BOND ETF	Aug. 21, 2026
Prospectus [Line Items]
Bar Chart and Performance Table [Heading]	FUND PERFORMANCE
Performance Narrative [Text Block]	The Fund is new and therefore does not have a performance history for a full calendar year. Performance information for the Fund will be provided once it has annual returns for a full calendar year. Updated performance information for the Fund will be available and may be obtained on the Fund’s website at etfs.ntam.northerntrust.com or by calling 1‑855‑353‑9383.
Performance One Year or Less [Text]	The Fund is new and therefore does not have a performance history for a full calendar year.
Performance Availability Website Address [Text]	etfs.ntam.northerntrust.com
Performance Availability Phone [Text]	1‑855‑353‑9383

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 4
-Subsection b
-Paragraph 2

Name:	oef_BarChartAndPerformanceTableHeading
Namespace Prefix:	oef_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph i

Name:	oef_PerformanceAvailabilityPhone
Namespace Prefix:	oef_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph i

Name:	oef_PerformanceAvailabilityWebSiteAddress
Namespace Prefix:	oef_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph i

Name:	oef_PerformanceNarrativeTextBlock
Namespace Prefix:	oef_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph i

Name:	oef_PerformanceOneYearOrLess
Namespace Prefix:	oef_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 1
-Subsection a

Name:	dei_LegalEntityAxis=nf_S000107710Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: