<SEC-DOCUMENT>0000860413-20-000101-index.html : 20200323
<SEC-HEADER>0000860413-20-000101.hdr.sgml : 20200323
<ACCEPTANCE-DATETIME>20200320192617
ACCESSION NUMBER:		0000860413-20-000101
CONFORMED SUBMISSION TYPE:	8-K
PUBLIC DOCUMENT COUNT:		21
CONFORMED PERIOD OF REPORT:	20200320
ITEM INFORMATION:		Regulation FD Disclosure
ITEM INFORMATION:		Financial Statements and Exhibits
FILED AS OF DATE:		20200323
DATE AS OF CHANGE:		20200320

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FIRST INTERSTATE BANCSYSTEM INC
		CENTRAL INDEX KEY:			0000860413
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				810331430
		STATE OF INCORPORATION:			MT
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		8-K
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34653
		FILM NUMBER:		20733308

	BUSINESS ADDRESS:	
		STREET 1:		P O BOX 30918
		STREET 2:		401 NO 31ST STREET
		CITY:			BILLINGS
		STATE:			MT
		ZIP:			59116-0918
		BUSINESS PHONE:		4062555300

	MAIL ADDRESS:	
		STREET 1:		P O BOX 30918
		STREET 2:		401 NO 31ST STREET
		CITY:			BILLINGS
		STATE:			MT
		ZIP:			59116-0918

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FIRST INTERSTATE BANCSYSTEM OF MONTANA INC
		DATE OF NAME CHANGE:	19930615
</SEC-HEADER>
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Document 1 - file: fibk-20200320x8k.htm

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Document 2 - file: hospitalitypresentation.htm

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<FILENAME>fibk-20200320.xsd
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Document 3 - file: fibk-20200320.xsd

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<FILENAME>fibk-20200320_cal.xml
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Document 4 - file: fibk-20200320_cal.xml

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Document 5 - file: fibk-20200320_def.xml

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Document 6 - file: fibk-20200320_lab.xml

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Document 9 - file: hospitalitypresentation002.jpg

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Document 10 - file: hospitalitypresentation003.jpg

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Document 11 - file: hospitalitypresentation004.jpg

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Document 12 - file: hospitalitypresentation005.jpg

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Document 13 - file: hospitalitypresentation006.jpg

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Document 14 - file: fibk-20200320x8k_htm.html

Document 14 - RAW XML: fibk-20200320x8k_htm.xml

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Document 15 - file: 0000860413-20-000101-xbrl.zip

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Document 16 - file: Financial_Report.xlsx

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Document 18 - file: Show.js

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Document 19 - file: MetaLinks.json

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Document 20 - file: FilingSummary.html

Document 20 - RAW XML: FilingSummary.xml

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Document 21 - file: R1.htm

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Document 22 - file: report.css

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