v3.25.2
Shareholder Report
 12 Months Ended
Jul. 31, 2025
USD ($)
Holding
Shareholder Report [Line Items]  
Document Type N-CSR
Amendment Flag false
Registrant Name Columbia Funds Series Trust I
Entity Central Index Key 0000773757
Entity Investment Company Type N-1A
Document Period End Date Jul. 31, 2025
Columbia Oregon Intermediate Municipal Bond Fund - Class A  
Shareholder Report [Line Items]  
Fund Name Columbia Oregon Intermediate Municipal Bond Fund
Class Name Class A
Trading Symbol COEAX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about Columbia Oregon Intermediate Municipal Bond Fund (the Fund) for the period of August 1, 2024 to July 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at
columbiathreadneedleus.com/resources/literature
. You can also request more information by contacting us at
1-800-345-6611.
Additional Information Email 1-800-345-6611
Additional Information Website columbiathreadneedleus.com/resources/literature
Expenses [Text Block]
What were the Fund costs for the reporting period?
(Based on a hypothetical $10,000 investment)
ClassCost of a $10,000 investmentCost paid as a percentage of a $10,000 investment
Class A
$
80		0.80
%
Expenses Paid, Amount $ 80
Expense Ratio, Percent 0.80%
Factors Affecting Performance [Text Block]
Management's Discussion of Fund Performance
The performance of Class A shares for the period presented is shown in the Average Annual Total Returns table.
Top Performance Contributors
Sector security selection
| Strong security selection in housing, airport, utility and education bonds contributed to the Fund’s performance relative to its benchmark.
Credit quality security selection
| Strong security selection in AA rated bonds was a positive contributor to benchmark-relative performance.
Sector allocation
| Overweights to the pre-refunded and housing sectors added to the Fund’s relative performance.
Credit quality allocation
| An underweight to AAA rated bonds added to relative performance.
Top Performance Detractors
Yield curve positioning
 
I
 
Heavy supply and market uncertainty resulted in a reshaping of the yield curve, driving the curve steeper as short rates declined and intermediate and long rates moved higher. The Fund’s yield curve positioning was the main detractor from performance, relative to its benchmark. Specifically, the Fund’s overweight to longer-intermediate maturity bonds (10 years and longer) detracted, as municipal market interest rates rose in this portion of the curve.
Sector security selection
| Security selection in the transportation and pre-refunded sectors detracted from relative performance.
Credit quality security selection
| Security selection in AAA and A rated bonds detracted from relative performance.
Credit quality allocation
| An overweight to AA bonds and underweights to A and BBB bonds detracted from relative performance.
Performance Past Does Not Indicate Future [Text] The Fund's past performance is not a good predictor of the Fund's future performance.
Line Graph [Table Text Block] Fund Performance - Growth of 10K
Average Annual Return [Table Text Block]
Average Annual Total Returns (%)1 year5 years10 years
Class A (excluding sales charges)0.82 (0.24
)
1.35
Class A (including sales charges)(2.22
)
(0.85
)
1.04
Bloomberg 3-15 Year Blend Municipal Bond Index1.86 0.54 2.16
Bloomberg Municipal Bond Index0.00 0.13 2.11
No Deduction of Taxes [Text Block] Performance does not reflect the deduction of taxes that a shareholder may pay on fund distributions or on the redemptions of fund shares.
Updated Performance Information Location [Text Block] Visit
columbiathreadneedleus.com/investment-products/mutual-funds
for more recent performance information.
Net Assets $ 285,046,389
Holdings Count | Holding 187
Advisory Fees Paid, Amount $ 1,403,974
Investment Company, Portfolio Turnover 12.00%
Additional Fund Statistics [Text Block]
Key Fund Statistics
Fund net assets
$
285,046,389
Total number of portfolio holdings
187
Management services fees
(represents 0.47% of Fund average net assets)
$
1,403,974
Portfolio turnover for the reporting period
12%
Holdings [Text Block]
Graphical Representation of Fund
 
Holdings
The tables below show the investment makeup of the Fund represented as a percentage of Fund net assets. Derivatives are excluded from the tables unless otherwise noted. The Fund's portfolio composition is subject to change.
Top Holdings
Oregon Health & Science University
07/01/2034 5.000%		2.7
%
City of Portland Water System
04/01/2030 4.000%		2.6
%
Tri-County Metropolitan Transportation District of Oregon
10/01/2032 5.000%		2.5
%
Oregon Health & Science University
07/01/2032 5.000%		1.9
%
City of Portland Sewer System
12/01/2042 5.000%		1.8
%
Puerto Rico Public Finance Corp.
08/01/2026 6.000%		1.8
%
State of Oregon Housing & Community Services Department
01/10/2048 4.000%		1.8
%
State of Oregon Department of Transportation
11/15/2037 5.000%		1.8
%
Port of Portland
07/01/2039 4.000%		1.7
%
Washington Clackamas & Yamhill Counties School District No. 88J
06/15/2031 5.000%		1.6
%
Asset Categories
Graphical Representation - Allocation 1 Chart
Largest Holdings [Text Block]
Top Holdings
Oregon Health & Science University
07/01/2034 5.000%		2.7
%
City of Portland Water System
04/01/2030 4.000%		2.6
%
Tri-County Metropolitan Transportation District of Oregon
10/01/2032 5.000%		2.5
%
Oregon Health & Science University
07/01/2032 5.000%		1.9
%
City of Portland Sewer System
12/01/2042 5.000%		1.8
%
Puerto Rico Public Finance Corp.
08/01/2026 6.000%		1.8
%
State of Oregon Housing & Community Services Department
01/10/2048 4.000%		1.8
%
State of Oregon Department of Transportation
11/15/2037 5.000%		1.8
%
Port of Portland
07/01/2039 4.000%		1.7
%
Washington Clackamas & Yamhill Counties School District No. 88J
06/15/2031 5.000%		1.6
%
Columbia Oregon Intermediate Municipal Bond Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Columbia Oregon Intermediate Municipal Bond Fund
Class Name Institutional Class
Trading Symbol CMBFX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about Columbia Oregon Intermediate Municipal Bond Fund (the Fund) for the period of August 1, 2024 to July 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at
columbiathreadneedleus.com/resources/literature
. You can also request more information by contacting us at
1-800-345-6611.
Additional Information Phone Number 1-800-345-6611
Additional Information Website columbiathreadneedleus.com/resources/literature
Expenses [Text Block]
What were the Fund costs for the reporting period?
(Based on a hypothetical $10,000 investment)
ClassCost of a $10,000 investmentCost paid as a percentage of a $10,000 investment
Institutional Class
$
55		0.55
%
Expenses Paid, Amount $ 55
Expense Ratio, Percent 0.55%
Factors Affecting Performance [Text Block]
Management's Discussion of Fund Performance
The performance of Institutional Class shares for the period presented is shown in the Average Annual Total Returns table.
Top Performance Contributors
Sector security selection
| Strong security selection in housing, airport, utility and education bonds contributed to the Fund’s performance relative to its benchmark.
Credit quality security selection
| Strong security selection in AA rated bonds was a positive contributor to benchmark-relative performance.
Sector allocation
| Overweights to the pre-refunded and housing sectors added to the Fund’s relative performance.
Credit quality allocation
| An underweight to AAA rated bonds added to relative performance.
Top Performance Detractors
Yield curve positioning
 
I
 
Heavy supply and market uncertainty resulted in a reshaping of the yield curve, driving the curve steeper as short rates declined and intermediate and long rates moved higher. The Fund’s yield curve positioning was the main detractor from performance, relative to its benchmark. Specifically, the Fund’s overweight to longer-intermediate maturity bonds (10 years and longer) detracted, as municipal market interest rates rose in this portion of the curve.
Sector security selection
| Security selection in the transportation and pre-refunded sectors detracted from relative performance.
Credit quality security selection
| Security selection in AAA and A rated bonds detracted from relative performance.
Credit quality allocation
| An overweight to AA bonds and underweights to A and BBB bonds detracted from relative performance.
Performance Past Does Not Indicate Future [Text] The Fund's past performance is not a good predictor of the Fund's future performance.
Line Graph [Table Text Block] Fund Performance - Growth of 10K
Average Annual Return [Table Text Block]
Average Annual Total Returns (%)1 year5 years10 years
Institutional Class1.07 0.01 1.60
Bloomberg 3-15 Year Blend Municipal Bond Index1.860.542.16
Bloomberg Municipal Bond Index0.00 0.13 2.11
No Deduction of Taxes [Text Block] Performance does not reflect the deduction of taxes that a shareholder may pay on fund distributions or on the redemptions of fund shares.
Updated Performance Information Location [Text Block] Visit
columbiathreadneedleus.com/investment-products/mutual-funds
for more recent performance information.
Net Assets $ 285,046,389
Holdings Count | Holding 187
Advisory Fees Paid, Amount $ 1,403,974
Investment Company, Portfolio Turnover 12.00%
Additional Fund Statistics [Text Block]
Key Fund Statistics
Fund net assets
$
285,046,389
Total number of portfolio holdings
187
Management services fees
(represents 0.47% of Fund average net assets)
$
1,403,974
Portfolio turnover for the reporting period
12%
Holdings [Text Block]
Graphical Representation of Fund
 
Holdings
The tables below show the investment makeup of the Fund represented as a percentage of Fund net assets. Derivatives are excluded from the tables unless otherwise noted. The Fund's portfolio composition is subject to change.
Top Holdings
Oregon Health & Science University
07/01/2034 5.000%		2.7
%
City of Portland Water System
04/01/2030 4.000%		2.6
%
Tri-County Metropolitan Transportation District of Oregon
10/01/2032 5.000%		2.5
%
Oregon Health & Science University
07/01/2032 5.000%		1.9
%
City of Portland Sewer System
12/01/2042 5.000%		1.8
%
Puerto Rico Public Finance Corp.
08/01/2026 6.000%		1.8
%
State of Oregon Housing & Community Services Department
01/10/2048 4.000%		1.8
%
State of Oregon Department of Transportation
11/15/2037 5.000%		1.8
%
Port of Portland
07/01/2039 4.000%		1.7
%
Washington Clackamas & Yamhill Counties School District No. 88J
06/15/2031 5.000%		1.6
%
Asset Categories
Graphical Representation - Allocation 1 Chart
Largest Holdings [Text Block]
Top Holdings
Oregon Health & Science University
07/01/2034 5.000%		2.7
%
City of Portland Water System
04/01/2030 4.000%		2.6
%
Tri-County Metropolitan Transportation District of Oregon
10/01/2032 5.000%		2.5
%
Oregon Health & Science University
07/01/2032 5.000%		1.9
%
City of Portland Sewer System
12/01/2042 5.000%		1.8
%
Puerto Rico Public Finance Corp.
08/01/2026 6.000%		1.8
%
State of Oregon Housing & Community Services Department
01/10/2048 4.000%		1.8
%
State of Oregon Department of Transportation
11/15/2037 5.000%		1.8
%
Port of Portland
07/01/2039 4.000%		1.7
%
Washington Clackamas & Yamhill Counties School District No. 88J
06/15/2031 5.000%		1.6
%
Columbia Oregon Intermediate Municipal Bond Fund - Institutional 2 Class  
Shareholder Report [Line Items]  
Fund Name Columbia Oregon Intermediate Municipal Bond Fund
Class Name Institutional 2 Class
Trading Symbol CODRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about Columbia Oregon Intermediate Municipal Bond Fund (the Fund) for the period of August 1, 2024 to July 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at
columbiathreadneedleus.com/resources/literature
. You can also request more information by contacting us at
1-800-345-6611.
Additional Information Phone Number 1-800-345-6611
Additional Information Website columbiathreadneedleus.com/resources/literature
Expenses [Text Block]
What were the Fund costs for the reporting period?
(Based on a hypothetical $10,000 investment)
ClassCost of a $10,000 investmentCost paid as a percentage of a $10,000 investment
Institutional 2 Class
$
53		0.53
%
Expenses Paid, Amount $ 53
Expense Ratio, Percent 0.53%
Factors Affecting Performance [Text Block]
Management's Discussion of Fund Performance
The performance of Institutional 2 Class shares for the period presented is shown in the Average Annual Total Returns table.
Top Performance Contributors
Sector security selection
| Strong security selection in housing, airport, utility and education bonds contributed to the Fund’s performance relative to its benchmark.
Credit quality security selection
| Strong security selection in AA rated bonds was a positive contributor to benchmark-relative performance.
Sector allocation
| Overweights to the pre-refunded and housing sectors added to the Fund’s relative performance.
Credit quality allocation
| An underweight to AAA rated bonds added to relative performance.
Top Performance Detractors
Yield curve positioning
 
I
 
Heavy supply and market uncertainty resulted in a reshaping of the yield curve, driving the curve steeper as short rates declined and intermediate and long rates moved higher. The Fund’s yield curve positioning was the main detractor from performance, relative to its benchmark. Specifically, the Fund’s overweight to longer-intermediate maturity bonds (10 years and longer) detracted, as municipal market interest rates rose in this portion of the curve.
Sector security selection
| Security selection in the transportation and pre-refunded sectors detracted from relative performance.
Credit quality security selection
| Security selection in AAA and A rated bonds detracted from relative performance.
Credit quality allocation
| An overweight to AA bonds and underweights to A and BBB bonds detracted from relative performance.
Performance Past Does Not Indicate Future [Text] The Fund's past performance is not a good predictor of the Fund's future performance.
Line Graph [Table Text Block] Fund Performance - Growth of 10K
Average Annual Return [Table Text Block]
Average Annual Total Returns (%)1 year5 years10 years
Institutional 2 Class1.10 0.04 1.63
Bloomberg 3-15 Year Blend Municipal Bond Index1.860.542.16
Bloomberg Municipal Bond Index0.00 0.13 2.11
No Deduction of Taxes [Text Block] Performance does not reflect the deduction of taxes that a shareholder may pay on fund distributions or on the redemptions of fund shares.
Updated Performance Information Location [Text Block] Visit
columbiathreadneedleus.com/investment-products/mutual-funds
for more recent performance information.
Net Assets $ 285,046,389
Holdings Count | Holding 187
Advisory Fees Paid, Amount $ 1,403,974
Investment Company, Portfolio Turnover 12.00%
Additional Fund Statistics [Text Block]
Key Fund Statistics
Fund net assets
$
285,046,389
Total number of portfolio holdings
187
Management services fees
(represents 0.47% of Fund average net assets)
$
1,403,974
Portfolio turnover for the reporting period
12%
Holdings [Text Block]
Graphical Representation of Fund
 
Holdings
The tables below show the investment makeup of the Fund represented as a percentage of Fund net assets. Derivatives are excluded from the tables unless otherwise noted. The Fund's portfolio composition is subject to change.
Top Holdings
Oregon Health & Science University
07/01/2034 5.000%		2.7
%
City of Portland Water System
04/01/2030 4.000%		2.6
%
Tri-County Metropolitan Transportation District of Oregon
10/01/2032 5.000%		2.5
%
Oregon Health & Science University
07/01/2032 5.000%		1.9
%
City of Portland Sewer System
12/01/2042 5.000%		1.8
%
Puerto Rico Public Finance Corp.
08/01/2026 6.000%		1.8
%
State of Oregon Housing & Community Services Department
01/10/2048 4.000%		1.8
%
State of Oregon Department of Transportation
11/15/2037 5.000%		1.8
%
Port of Portland
07/01/2039 4.000%		1.7
%
Washington Clackamas & Yamhill Counties School District No. 88J
06/15/2031 5.000%		1.6
%
Asset Categories
Graphical Representation - Allocation 1 Chart
Largest Holdings [Text Block]
Top Holdings
Oregon Health & Science University
07/01/2034 5.000%		2.7
%
City of Portland Water System
04/01/2030 4.000%		2.6
%
Tri-County Metropolitan Transportation District of Oregon
10/01/2032 5.000%		2.5
%
Oregon Health & Science University
07/01/2032 5.000%		1.9
%
City of Portland Sewer System
12/01/2042 5.000%		1.8
%
Puerto Rico Public Finance Corp.
08/01/2026 6.000%		1.8
%
State of Oregon Housing & Community Services Department
01/10/2048 4.000%		1.8
%
State of Oregon Department of Transportation
11/15/2037 5.000%		1.8
%
Port of Portland
07/01/2039 4.000%		1.7
%
Washington Clackamas & Yamhill Counties School District No. 88J
06/15/2031 5.000%		1.6
%
Columbia Oregon Intermediate Municipal Bond Fund - Institutional 3 Class  
Shareholder Report [Line Items]  
Fund Name Columbia Oregon Intermediate Municipal Bond Fund
Class Name Institutional 3 Class
Trading Symbol CORYX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about Columbia Oregon Intermediate Municipal Bond Fund (the Fund) for the period of August 1, 2024 to July 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at
columbiathreadneedleus.com/resources/literature
. You can also request more information by contacting us at
1-800-345-6611.
Additional Information Phone Number 1-800-345-6611
Additional Information Website columbiathreadneedleus.com/resources/literature
Expenses [Text Block]
What were the Fund costs for the reporting period?
(Based on a hypothetical $10,000 investment)
ClassCost of a $10,000 investmentCost paid as a percentage of a $10,000 investment
Institutional 3 Class
$
48		0.48
%
Expenses Paid, Amount $ 48
Expense Ratio, Percent 0.48%
Factors Affecting Performance [Text Block]
Management's Discussion of Fund Performance
The performance of Institutional 3 Class shares for the period presented is shown in the Average Annual Total Returns table.
Top Performance Contributors
Sector security selection
| Strong security selection in housing, airport, utility and education bonds contributed to the Fund’s performance relative to its benchmark.
Credit quality security selection
| Strong security selection in AA rated bonds was a positive contributor to benchmark-relative performance.
Sector allocation
| Overweights to the pre-refunded and housing sectors added to the Fund’s relative performance.
Credit quality allocation
| An underweight to AAA rated bonds added to relative performance.
Top Performance Detractors
Yield curve positioning
 
I
 
Heavy supply and market uncertainty resulted in a reshaping of the yield curve, driving the curve steeper as short rates declined and intermediate and long rates moved higher. The Fund’s yield curve positioning was the main detractor from performance, relative to its benchmark. Specifically, the Fund’s overweight to longer-intermediate maturity bonds (10 years and longer) detracted, as municipal market interest rates rose in this portion of the curve.
Sector security selection
| Security selection in the transportation and pre-refunded sectors detracted from relative performance.
Credit quality security selection
| Security selection in AAA and A rated bonds detracted from relative performance.
Credit quality allocation
| An overweight to AA bonds and underweights to A and BBB bonds detracted from relative performance.
Performance Past Does Not Indicate Future [Text] The Fund's past performance is not a good predictor of the Fund's future performance.
Line Graph [Table Text Block] Fund Performance - Growth of 10K
Average Annual Return [Table Text Block]
Average Annual Total Returns (%)1 year5 years10
years
Institutional 3
Class
(a)
1.15 0.09 1.67
Bloomberg 3-15 Year Blend Municipal Bond Index1.86 0.54 2.16
Bloomberg Municipal Bond Index0.00 0.13 2.11
(a)
The returns shown for periods prior to March 1, 2017 (including Since Fund Inception returns, if shown) include the returns of Institutional Class. These returns are adjusted to reflect any higher class-related operating expenses of the newer share classes, as applicable. Please visit
columbiathreadneedleus.com/investment-products/mutual-funds/appended-performance
for more information.
No Deduction of Taxes [Text Block] Performance does not reflect the deduction of taxes that a shareholder may pay on fund distributions or on the redemptions of fund shares.
Updated Performance Information Location [Text Block] Visit
columbiathreadneedleus.com/investment-products/mutual-funds
for more recent performance information.
Net Assets $ 285,046,389
Holdings Count | Holding 187
Advisory Fees Paid, Amount $ 1,403,974
Investment Company, Portfolio Turnover 12.00%
Additional Fund Statistics [Text Block]
Key Fund Statistics
Fund net assets
$
285,046,389
Total number of portfolio holdings
187
Management services fees
(represents 0.47% of Fund average net assets)
$
1,403,974
Portfolio turnover for the reporting period
12%
Holdings [Text Block]
Graphical Representation of Fund
 
Holdings
The tables below show the investment makeup of the Fund represented as a percentage of Fund net assets. Derivatives are excluded from the tables unless otherwise noted. The Fund's portfolio composition is subject to change.
Top Holdings
Oregon Health & Science University
07/01/2034 5.000%		2.7
%
City of Portland Water System
04/01/2030 4.000%		2.6
%
Tri-County Metropolitan Transportation District of Oregon
10/01/2032 5.000%		2.5
%
Oregon Health & Science University
07/01/2032 5.000%		1.9
%
City of Portland Sewer System
12/01/2042 5.000%		1.8
%
Puerto Rico Public Finance Corp.
08/01/2026 6.000%		1.8
%
State of Oregon Housing & Community Services Department
01/10/2048 4.000%		1.8
%
State of Oregon Department of Transportation
11/15/2037 5.000%		1.8
%
Port of Portland
07/01/2039 4.000%		1.7
%
Washington Clackamas & Yamhill Counties School District No. 88J
06/15/2031 5.000%		1.6
%
Asset Categories
Graphical Representation - Allocation 1 Chart
Largest Holdings [Text Block]
Top Holdings
Oregon Health & Science University
07/01/2034 5.000%		2.7
%
City of Portland Water System
04/01/2030 4.000%		2.6
%
Tri-County Metropolitan Transportation District of Oregon
10/01/2032 5.000%		2.5
%
Oregon Health & Science University
07/01/2032 5.000%		1.9
%
City of Portland Sewer System
12/01/2042 5.000%		1.8
%
Puerto Rico Public Finance Corp.
08/01/2026 6.000%		1.8
%
State of Oregon Housing & Community Services Department
01/10/2048 4.000%		1.8
%
State of Oregon Department of Transportation
11/15/2037 5.000%		1.8
%
Port of Portland
07/01/2039 4.000%		1.7
%
Washington Clackamas & Yamhill Counties School District No. 88J
06/15/2031 5.000%		1.6
%
Columbia Oregon Intermediate Municipal Bond Fund - Class S  
Shareholder Report [Line Items]  
Fund Name Columbia Oregon Intermediate Municipal Bond Fund
Class Name Class S
Trading Symbol CMBCX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about Columbia Oregon Intermediate Municipal Bond Fund (the Fund) for the period of October 2, 2024 to July 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at
columbiathreadneedleus.com/resources/literature
. You can also request more information by contacting us at
1-800-345-6611.
Additional Information Phone Number 1-800-345-6611
Additional Information Website columbiathreadneedleus.com/resources/literature
Expenses [Text Block]
What were the Fund costs for the reporting period?
(Based on a hypothetical $10,000 investment)
ClassCost of a $10,000 investmentCost paid as a percentage of a $10,000 investment
Class S
$
45
(a)
0.55
%
(b)
(a)
Based on operations from October 2, 2024 (commencement of operations) through the stated period end. Had the class been open for the entire reporting period, expenses shown in the table above would have been higher.
(b)
Annualized.
Expenses Paid, Amount $ 45 [1]
Expense Ratio, Percent 0.55% [2]
Factors Affecting Performance [Text Block]
Management's Discussion of Fund Performance
The performance of Class S shares for the period presented is shown in the Average Annual Total Returns table.
Top Performance Contributors
Sector security selection
| Strong security selection in housing, airport, utility and education bonds contributed to the Fund’s performance relative to its benchmark.
Credit quality security selection
| Strong security selection in AA rated bonds was a positive contributor to benchmark-relative performance.
Sector allocation
| Overweights to the pre-refunded and housing sectors added to the Fund’s relative performance.
Credit quality allocation
| An underweight to AAA rated bonds added to relative performance.
Top Performance Detractors
Yield curve positioning
 
I
 
Heavy supply and market uncertainty resulted in a reshaping of the yield curve, driving the curve steeper as short rates declined and intermediate and long rates moved higher. The Fund’s yield curve positioning was the main detractor from performance, relative to its benchmark. Specifically, the Fund’s overweight to longer-intermediate maturity bonds (10 years and longer) detracted, as municipal market interest rates rose in this portion of the curve.
Sector security selection
| Security selection in the transportation and pre-refunded sectors detracted from relative performance.
Credit quality security selection
| Security selection in AAA and A rated bonds detracted from relative performance.
Credit quality allocation
| An overweight to AA bonds and underweights to A and BBB bonds detracted from relative performance.
Performance Past Does Not Indicate Future [Text] The Fund's past performance is not a good predictor of the Fund's future performance.
Line Graph [Table Text Block] Fund Performance - Growth of 10K
Average Annual Return [Table Text Block]
Average Annual Total Returns (%)1 year5 years10 years
Class
S
(a)
1.07 0.01 1.60
Bloomberg 3-15 Year Blend Municipal Bond Index1.86 0.54 2.16
Bloomberg Municipal Bond Index0.00 0.13 2.11
(a)
The returns shown for periods prior to October 2, 2024 (including Since Fund Inception returns, if shown) include the returns of Institutional Class. These returns are adjusted to reflect any higher class-related operating expenses of the newer share classes, as applicable. Please visit
columbiathreadneedleus.com/investment-products/mutual-funds/appended-performance
for more information.
No Deduction of Taxes [Text Block] Performance does not reflect the deduction of taxes that a shareholder may pay on fund distributions or on the redemptions of fund shares.
Updated Performance Information Location [Text Block] Visit
columbiathreadneedleus.com/investment-products/mutual-funds
for more recent performance information.
Net Assets $ 285,046,389
Holdings Count | Holding 187
Advisory Fees Paid, Amount $ 1,403,974
Investment Company, Portfolio Turnover 12.00%
Additional Fund Statistics [Text Block]
Key Fund Statistics
Fund net assets
$
285,046,389
Total number of portfolio holdings
187
Management services fees
(represents 0.47% of Fund average net assets)
$
1,403,974
Portfolio turnover for the reporting period
12%
Holdings [Text Block]
Graphical Representation of Fund
 
Holdings
The tables below show the investment makeup of the Fund represented as a percentage of Fund net assets. Derivatives are excluded from the tables unless otherwise noted. The Fund's portfolio composition is subject to change.
Top Holdings
Oregon Health & Science University
07/01/2034 5.000%		2.7
%
City of Portland Water System
04/01/2030 4.000%		2.6
%
Tri-County Metropolitan Transportation District of Oregon
10/01/2032 5.000%		2.5
%
Oregon Health & Science University
07/01/2032 5.000%		1.9
%
City of Portland Sewer System
12/01/2042 5.000%		1.8
%
Puerto Rico Public Finance Corp.
08/01/2026 6.000%		1.8
%
State of Oregon Housing & Community Services Department
01/10/2048 4.000%		1.8
%
State of Oregon Department of Transportation
11/15/2037 5.000%		1.8
%
Port of Portland
07/01/2039 4.000%		1.7
%
Washington Clackamas & Yamhill Counties School District No. 88J
06/15/2031 5.000%		1.6
%
Asset Categories
Graphical Representation - Allocation 1 Chart
Largest Holdings [Text Block]
Top Holdings
Oregon Health & Science University
07/01/2034 5.000%		2.7
%
City of Portland Water System
04/01/2030 4.000%		2.6
%
Tri-County Metropolitan Transportation District of Oregon
10/01/2032 5.000%		2.5
%
Oregon Health & Science University
07/01/2032 5.000%		1.9
%
City of Portland Sewer System
12/01/2042 5.000%		1.8
%
Puerto Rico Public Finance Corp.
08/01/2026 6.000%		1.8
%
State of Oregon Housing & Community Services Department
01/10/2048 4.000%		1.8
%
State of Oregon Department of Transportation
11/15/2037 5.000%		1.8
%
Port of Portland
07/01/2039 4.000%		1.7
%
Washington Clackamas & Yamhill Counties School District No. 88J
06/15/2031 5.000%		1.6
%
[1] Based on operations from October 2, 2024 (commencement of operations) through the stated period end. Had the class been open for the entire reporting period, expenses shown in the table above would have been higher.
[2] Annualized.