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  <xs:element id="fibk_DepositsExcludingTimeDepositsFairValueDisclosure" abstract="false" name="DepositsExcludingTimeDepositsFairValueDisclosure" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
