XML 44 R2.htm IDEA: XBRL DOCUMENT v3.24.3
Shareholder Report
 12 Months Ended
Aug. 31, 2024
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 Aug. 31, 2024
Columbia Strategic Income Fund - Class A  
Shareholder Report [Line Items]  
Fund Name Columbia Strategic Income Fund
Class Name Class A
Trading Symbol COSIX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about Columbia Strategic Income Fund (the Fund) for the period of September 1, 2023 to August 31, 2024.
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 A
$
98		0.93
%
Expenses Paid, Amount $ 98
Expense Ratio, Percent 0.93%
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
Duration
| Duration and curve positioning added slightly to performance, as the yield for 10 Year Treasury bonds fell by approximately 20 basis points over the period while the yield for 3 Year Treasury bonds fell by 80 basis points. (A basis point is 1/100 of one percent.) Although the Fund held less overall duration than the benchmark, it held more duration in the short-to-intermediate part of the curve than the benchmark.
Allocations
| Positive contributions to the Fund’s performance were driven by out-of-benchmark exposure to high-yield corporates, non-agency mortgage-backed securities (MBS), floating rate bank loans, and emerging market debt securities.
Security selection
| Security selection was also a positive contributor to performance, with contributions coming from agency MBS, investment-grade corporates, and asset-backed securities.
Security selection
| Detractors in security selection came from the commercial mortgage-backed securities and emerging market debt sectors.
Performance Past Does Not Indicate Future [Text] Past performance does not guarantee 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) 10.542.593.12
Class A (including sales charges) 5.311.592.62
Bloomberg U.S. Aggregate Bond Index7.30 (0.04
)
1.64
ICE BofA US Cash Pay High Yield Constrained Index12.37 4.24 4.55
FTSE Non-U.S. World Government Bond (All Maturities) Index – Unhedged5.46 (4.10
)
(1.73
)
JPMorgan Emerging Markets Bond Index - Global12.69 0.76 2.69
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 $ 5,661,996,222
Holdings Count | Holding 1,163
Advisory Fees Paid, Amount $ 29,323,389
Investment Company, Portfolio Turnover 272.00%
Additional Fund Statistics [Text Block]
Fund net assets
$
5,661,996,222
Total number of portfolio holdings1,163
Management services fees
(represents 0.56% of Fund average net assets)
$
29,323,389
Portfolio turnover for the reporting period 272%
Portfolio turnover for the reporting period excluding to be announced (TBA) securities52%
Holdings [Text Block]
Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a
security
is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is applied to those bonds that would otherwise be not rated. When a bond is not rated by any rating agency, it is designated as “Not rated.” Credit quality ratings assigned by a rating agency are subjective opinions, not statements of fact, and are subject to change, including daily.
Derivative Exposure
Long
Credit Risk0.9
%
Interest Rate Risk50.7
%
Short
Credit Risk2.2
%
Foreign Exchange Risk0.4
%
Interest Rate Risk70.8
%
Asset Categories
Graphical Representation - Allocation 1 Chart
Credit Quality
Graphical Representation - Allocation 2 Chart
Credit Quality Explanation [Text Block]
Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a
security
is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is applied to those bonds that would otherwise be not rated. When a bond is not rated by any rating agency, it is designated as “Not rated.” Credit quality ratings assigned by a rating agency are subjective opinions, not statements of fact, and are subject to change, including daily.
Updated Prospectus Web Address columbiathreadneedleus.com/investment-products/mutual-funds
Columbia Strategic Income Fund - Advisor Class  
Shareholder Report [Line Items]  
Fund Name Columbia Strategic Income Fund
Class Name Advisor Class
Trading Symbol CMNRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about Columbia Strategic Income Fund (the Fund) for the period of September 1, 2023 to August 31, 2024.
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
Advisor Class
$
71		0.68
%
Expenses Paid, Amount $ 71
Expense Ratio, Percent 0.68%
Factors Affecting Performance [Text Block]
Management's Discussion of Fund Performance
The performance of Advisor Class shares for the period presented is shown in the Average Annual Total Returns table.
Top Performance Contributors
Duration
| Duration and curve positioning added slightly to performance, as the yield for 10 Year Treasury bonds fell by approximately 20 basis points over the period while the yield for 3 Year Treasury bonds fell by 80 basis points. (A basis point is 1/100 of one percent.) Although the Fund held less overall duration than the benchmark, it held more duration in the short-to-intermediate part of the curve than the benchmark.
Allocations
| Positive contributions to the Fund’s performance were driven by out-of-benchmark exposure to high-yield corporates, non-agency mortgage-backed securities (MBS), floating rate bank loans, and emerging market debt securities.
Security selection
| Security selection was also a positive contributor to performance, with contributions coming from agency MBS, investment-grade corporates, and asset-backed securities.
Security selection
| Detractors in security selection came from the commercial mortgage-backed securities and emerging market debt sectors.
Performance Past Does Not Indicate Future [Text] Past performance does not guarantee 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
Advisor Class 10.862.853.38
Bloomberg U.S. Aggregate Bond Index7.30 (0.04
)
1.64
ICE BofA US Cash Pay High Yield Constrained Index12.37 4.24 4.55
FTSE Non-U.S. World Government Bond (All Maturities) Index – Unhedged5.46 (4.10
)
(1.73
)
JPMorgan Emerging Markets Bond Index - Global12.69 0.76 2.69
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 $ 5,661,996,222
Holdings Count | Holding 1,163
Advisory Fees Paid, Amount $ 29,323,389
Investment Company, Portfolio Turnover 272.00%
Additional Fund Statistics [Text Block]
Key Fund Statistics
Fund net assets
$
5,661,996,222
Total number of portfolio holdings1,163
Management services fees
(represents 0.56% of Fund average net assets)
$
29,323,389
Portfolio turnover for the reporting period 272%
Portfolio turnover for the reporting period excluding to be announced (TBA) securities52%
Holdings [Text Block]
Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a security is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is appli
ed
to those bonds that would otherwise be not rated. When a bond is not rated by any rating agency, it is designated as “Not rated.” Credit quality ratings assigned by a rating agency are subjective opinions, not statements of fact, and are subject to change, including daily.
Derivative Exposure
Long
Credit Risk0.9
%
Interest Rate Risk50.7
%
Short
Credit Risk2.2
%
Foreign Exchange Risk0.4
%
Interest Rate Risk70.8
%
Asset Categories
Graphical Representation - Allocation 1 Chart
Credit Quality
Graphical Representation - Allocation 2 Chart
Credit Quality Explanation [Text Block] Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a security is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is appli
ed
to those bonds that would otherwise be not rated. When a bond is not rated by any rating agency, it is designated as “Not rated.” Credit quality ratings assigned by a rating agency are subjective opinions, not statements of fact, and are subject to change, including daily.
Updated Prospectus Web Address columbiathreadneedleus.com/investment-products/mutual-funds
Columbia Strategic Income Fund - Class C  
Shareholder Report [Line Items]  
Fund Name Columbia Strategic Income Fund
Class Name Class C
Trading Symbol CLSCX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about Columbia Strategic Income Fund (the Fund) for the period of September 1, 2023 to August 31, 2024.
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 C
$
176		1.68
%
Expenses Paid, Amount $ 176
Expense Ratio, Percent 1.68%
Factors Affecting Performance [Text Block]
Management's Discussion of Fund Performance
The performance of Class C shares for the period presented is shown in the Average Annual Total Returns table.
Top Performance Contributors
Duration
| Duration and curve positioning added slightly to performance, as the yield for 10 Year Treasury bonds fell by approximately 20 basis points over the period while the yield for 3 Year Treasury bonds fell by 80 basis points. (A basis point is 1/100 of one percent.) Although the Fund held less overall duration than the benchmark, it held more duration in the short-to-intermediate part of the curve than the benchmark.
Allocations
| Positive contributions to the Fund’s performance were driven by out-of-benchmark exposure to high-yield corporates, non-agency mortgage-backed securities (MBS), floating rate bank loans, and emerging market debt securities.
Security selection
| Security selection was also a positive contributor to performance, with contributions coming from agency MBS, investment-grade corporates, and asset-backed securities.
Security selection
| Detractors in security selection came from the commercial mortgage-backed securities and emerging market debt sectors.
Performance Past Does Not Indicate Future [Text] Past performance does not guarantee 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 C (excluding sales charges) 9.731.822.34
Class C (including sales charges) 8.731.822.34
Bloomberg U.S. Aggregate Bond Index7.30 (0.04
)
1.64
ICE BofA US Cash Pay High Yield Constrained Index12.37 4.24 4.55
FTSE Non-U.S. World Government Bond (All Maturities) Index – Unhedged5.46 (4.10
)
(1.73
)
JPMorgan Emerging Markets Bond Index - Global12.69 0.76 2.69
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 $ 5,661,996,222
Holdings Count | Holding 1,163
Advisory Fees Paid, Amount $ 29,323,389
Investment Company, Portfolio Turnover 272.00%
Additional Fund Statistics [Text Block]
Key Fund Statistics
Fund net assets
$
5,661,996,222
Total number of portfolio holdings1,163
Management services fees
(represents 0.56% of Fund average net assets)
$
29,323,389
Portfolio turnover for the reporting period 272%
Portfolio turnover for the reporting period excluding to be announced (TBA) securities52%
Holdings [Text Block]
Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a security is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is applied to those bonds that would otherwise be not rated. When a bond is not rated by any rating agency, it is designated as “Not rated.” Credit quality ratings assigned by a rating agency are subjective opinions, not statements of fact, and are subject to change, including daily.
Derivative Exposure
Long
Credit Risk0.9
%
Interest Rate Risk50.7
%
Short
Credit Risk2.2
%
Foreign Exchange Risk0.4
%
Interest Rate Risk70.8
%
Asset Categories
Graphical Representation - Allocation 1 Chart
Credit Quality
Graphical Representation - Allocation 2 Chart
Credit Quality Explanation [Text Block] Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a security is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is applied to those bonds that would otherwise be not rated. When a bond is not rated by any rating agency, it is designated as “Not rated.” Credit quality ratings assigned by a rating agency are subjective opinions, not statements of fact, and are subject to change, including daily.
Updated Prospectus Web Address columbiathreadneedleus.com/investment-products/mutual-funds
Columbia Strategic Income Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Columbia Strategic Income Fund
Class Name Institutional Class
Trading Symbol LSIZX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about Columbia Strategic Income Fund (the Fund) for the period of September 1, 2023 to August 31, 2024.
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
$
71		0.68
%
Expenses Paid, Amount $ 71
Expense Ratio, Percent 0.68%
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
Duration
| Duration and curve positioning added slightly to performance, as the yield for 10 Year Treasury bonds fell by approximately 20 basis points over the period while the yield for 3 Year Treasury bonds fell by 80 basis points. (A basis point is 1/100 of one percent.) Although the Fund held less overall duration than the benchmark, it held more duration in the short-to-intermediate part of the curve than the benchmark.
Allocations
| Positive contributions to the Fund’s performance were driven by out-of-benchmark exposure to high-yield corporates, non-agency mortgage-backed securities (MBS), floating rate bank loans, and emerging market debt securities.
Security selection
| Security selection was also a positive contributor to performance, with contributions coming from agency MBS, investment-grade corporates, and asset-backed securities.
Security selection
| Detractors in security selection came from the commercial mortgage-backed securities and emerging market debt sectors.
Performance Past Does Not Indicate Future [Text] Past performance does not guarantee 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 Class 10.842.833.37
Bloomberg U.S. Aggregate Bond Index7.30 (0.04
)
1.64
ICE BofA US Cash Pay High Yield Constrained Index12.37 4.24 4.55
FTSE Non-U.S. World Government Bond (All Maturities) Index – Unhedged5.46 (4.10
)
(1.73
)
JPMorgan Emerging Markets Bond Index - Global12.69 0.76 2.69
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 $ 5,661,996,222
Holdings Count | Holding 1,163
Advisory Fees Paid, Amount $ 29,323,389
Investment Company, Portfolio Turnover 272.00%
Additional Fund Statistics [Text Block]
Key Fund Statistics
Fund net assets
$
5,661,996,222
Total number of portfolio holdings1,163
Management services fees
(represents 0.56% of Fund average net assets)
$
29,323,389
Portfolio turnover for the reporting period 272%
Portfolio turnover for the reporting period excluding to be announced (TBA) securities52%
Holdings [Text Block]
Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a security is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is applied to those bonds that would otherwise be not rated. When a bond is not rated by any rating agency, it is designated as “Not rated.” Credit quality ratings assigned by a rating age
nc
y are subjective opinions, not statements of fact, and are subject to change, including daily.
Derivative Exposure
Long
Credit Risk0.9
%
Interest Rate Risk50.7
%
Short
Credit Risk2.2
%
Foreign Exchange Risk0.4
%
Interest Rate Risk70.8
%
Asset Categories
Graphical Representation - Allocation 1 Chart
Credit Quality
Graphical Representation - Allocation 2 Chart
Credit Quality Explanation [Text Block] Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a security is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is applied to those bonds that would otherwise be not rated. When a bond is not rated by any rating agency, it is designated as “Not rated.” Credit quality ratings assigned by a rating age
nc
y are subjective opinions, not statements of fact, and are subject to change, including daily.
Updated Prospectus Web Address columbiathreadneedleus.com/investment-products/mutual-funds
Columbia Strategic Income Fund - Institutional 2 Class  
Shareholder Report [Line Items]  
Fund Name Columbia Strategic Income Fund
Class Name Institutional 2 Class
Trading Symbol CTIVX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about Columbia Strategic Income Fund (the Fund) for the period of September 1, 2023 to August 31, 2024.
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
$
67		0.64
%
Expenses Paid, Amount $ 67
Expense Ratio, Percent 0.64%
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
Duration
| Duration and curve positioning added slightly to performance, as the yield for 10 Year Treasury bonds fell by approximately 20 basis points over the period while the yield for 3 Year Treasury bonds fell by 80 basis points. (A basis point is 1/100 of one percent.) Although the Fund held less overall duration than the benchmark, it held more duration in the short-to-intermediate part of the curve than the benchmark.
Allocations
| Positive contributions to the Fund’s performance were driven by out-of-benchmark exposure to high-yield corporates, non-agency mortgage-backed securities (MBS), floating rate bank loans, and emerging market debt securities.
Security selection
| Security selection was also a positive contributor to performance, with contributions coming from agency MBS, investment-grade corporates, and asset-backed securities.
Security selection
| Detractors in security selection came from the commercial mortgage-backed securities and emerging market debt sectors.
Performance Past Does Not Indicate Future [Text] Past performance does not guarantee 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 Class 10.882.893.44
Bloomberg U.S. Aggregate Bond Index7.30 (0.04
)
1.64
ICE BofA US Cash Pay High Yield Constrained Index12.37 4.24 4.55
FTSE Non-U.S. World Government Bond (All Maturities) Index – Unhedged5.46 (4.10
)
(1.73
)
JPMorgan Emerging Markets Bond Index - Global12.69 0.76 2.69
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 $ 5,661,996,222
Holdings Count | Holding 1,163
Advisory Fees Paid, Amount $ 29,323,389
Investment Company, Portfolio Turnover 272.00%
Additional Fund Statistics [Text Block]
Key Fund Statistics
Fund net assets
$
5,661,996,222
Total number of portfolio holdings1,163
Management services fees
(represents 0.56% of Fund average net assets)
$
29,323,389
Portfolio turnover for the reporting period 272%
Portfolio turnover for the reporting period excluding to be announced (TBA) securities52%
Holdings [Text Block]
Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a security is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is applied to those bonds that would otherwise be not rated. When a b
on
d is not rated by any rating agency, it is designated as “Not rated.” Credit quality ratings assigned by a rating agency are subjective opinions, not statements of fact, and are subject to change, including daily.
Derivative Exposure
Long
Credit Risk0.9
%
Interest Rate Risk50.7
%
Short
Credit Risk2.2
%
Foreign Exchange Risk0.4
%
Interest Rate Risk70.8
%
Asset Categories
Graphical Representation - Allocation 1 Chart
Credit Quality
Graphical Representation - Allocation 2 Chart
Credit Quality Explanation [Text Block] Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a security is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is applied to those bonds that would otherwise be not rated. When a b
on
d is not rated by any rating agency, it is designated as “Not rated.” Credit quality ratings assigned by a rating agency are subjective opinions, not statements of fact, and are subject to change, including daily.
Updated Prospectus Web Address columbiathreadneedleus.com/investment-products/mutual-funds
Columbia Strategic Income Fund - Institutional 3 Class  
Shareholder Report [Line Items]  
Fund Name Columbia Strategic Income Fund
Class Name Institutional 3 Class
Trading Symbol CPHUX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about Columbia Strategic Income Fund (the Fund) for the period of September 1, 2023 to August 31, 2024.
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
$
63		0.60
%
Expenses Paid, Amount $ 63
Expense Ratio, Percent 0.60%
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
Duration
| Duration and curve positioning added slightly to performance, as the yield for 10 Year Treasury bonds fell by approximately 20 basis points over the period while the yield for 3 Year Treasury bonds fell by 80 basis points. (A basis point is 1/100 of one percent.) Although the Fund held less overall duration than the benchmark, it held more duration in the short-to-intermediate part of the curve than the benchmark.
Allocations
| Positive contributions to the Fund’s performance were driven by out-of-benchmark exposure to high-yield corporates, non-agency mortgage-backed securities (MBS), floating rate bank loans, and emerging market debt securities.
Security selection
| Security selection was also a positive contributor to performance, with contributions coming from agency MBS, investment-grade corporates, and asset-backed securities.
Security selection
| Detractors in security selection came from the commercial mortgage-backed securities and emerging market debt sectors.
Performance Past Does Not Indicate Future [Text] Past performance does not guarantee 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 10.932.933.47
Bloomberg U.S. Aggregate Bond Index7.30 (0.04
)
1.64
ICE BofA US Cash Pay High Yield Constrained Index12.37 4.24 4.55
FTSE Non-U.S. World Government Bond (All Maturities) Index – Unhedged5.46 (4.10
)
(1.73
)
JPMorgan Emerging Markets Bond Index - Global12.69 0.76 2.69
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 $ 5,661,996,222
Holdings Count | Holding 1,163
Advisory Fees Paid, Amount $ 29,323,389
Investment Company, Portfolio Turnover 272.00%
Additional Fund Statistics [Text Block]
Key Fund Statistics
Fund net assets
$
5,661,996,222
Total number of portfolio holdings1,163
Management services fees
(represents 0.56% of Fund average net assets)
$
29,323,389
Portfolio turnover for the reporting period 272%
Portfolio turnover for the reporting period excluding to be announced (TBA) securities52%
Holdings [Text Block]
Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a security is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is applied to those bonds that would otherwise be not rated. When a bond is not rated by any rating agency, it is designated as “Not rated.” Credit quality ratings assigned by a rating agency are subjective opinions, not statements
of f
act, and are subject to change, including daily.
Derivative Exposure
Long
Credit Risk0.9
%
Interest Rate Risk50.7
%
Short
Credit Risk2.2
%
Foreign Exchange Risk0.4
%
Interest Rate Risk70.8
%
Asset Categories
Graphical Representation - Allocation 1 Chart
Credit Quality
Graphical Representation - Allocation 2 Chart
Credit Quality Explanation [Text Block] Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a security is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is applied to those bonds that would otherwise be not rated. When a bond is not rated by any rating agency, it is designated as “Not rated.” Credit quality ratings assigned by a rating agency are subjective opinions, not statements
of f
act, and are subject to change, including daily.
Updated Prospectus Web Address columbiathreadneedleus.com/investment-products/mutual-funds
Columbia Strategic Income Fund - Class R  
Shareholder Report [Line Items]  
Fund Name Columbia Strategic Income Fund
Class Name Class R
Trading Symbol CSNRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about Columbia Strategic Income Fund (the Fund) for the period of September 1, 2023 to August 31, 2024.
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 R
$
124		1.18
%
Expenses Paid, Amount $ 124
Expense Ratio, Percent 1.18%
Factors Affecting Performance [Text Block]
Management's Discussion of Fund Performance
The performance of Class R shares for the period presented is shown in the Average Annual Total Returns table.
Top Performance Contributors
Duration
| Duration and curve positioning added slightly to performance, as the yield for 10 Year Treasury bonds fell by approximately 20 basis points over the period while the yield for 3 Year Treasury bonds fell by 80 basis points. (A basis point is 1/100 of one percent.) Although the Fund held less overall duration than the benchmark, it held more duration in the short-to-intermediate part of the curve than the benchmark.
Allocations
| Positive contributions to the Fund’s performance were driven by out-of-benchmark exposure to high-yield corporates, non-agency mortgage-backed securities (MBS), floating rate bank loans, and emerging market debt securities.
Security selection
| Security selection was also a positive contributor to performance, with contributions coming from agency MBS, investment-grade corporates, and asset-backed securities.
Security selection
| Detractors in security selection came from the commercial mortgage-backed securities and emerging market debt sectors.
Performance Past Does Not Indicate Future [Text] Past performance does not guarantee 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 R 10.282.312.86
Bloomberg U.S. Aggregate Bond Index7.30 (0.04
)
1.64
ICE BofA US Cash Pay High Yield Constrained Index12.37 4.24 4.55
FTSE Non-U.S. World Government Bond (All Maturities) Index – Unhedged5.46 (4.10
)
(1.73
)
JPMorgan Emerging Markets Bond Index - Global12.690.76 2.69
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 $ 5,661,996,222
Holdings Count | Holding 1,163
Advisory Fees Paid, Amount $ 29,323,389
Investment Company, Portfolio Turnover 272.00%
Additional Fund Statistics [Text Block]
Key Fund Statistics
Fund net assets
$
5,661,996,222
Total number of portfolio holdings1,163
Management services fees
(represents 0.56% of Fund average net assets)
$
29,323,389
Portfolio turnover for the reporting period 272%
Portfolio turnover for the reporting period excluding to be announced (TBA) securities52%
Holdings [Text Block]
Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a security is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is applied to those bonds that would otherwise be not rated. When a bond is not rated by any rating agency, it is designated as “Not rated.”
Credit
quality ratings assigned by a rating agency are subjective opinions, not statements of fact, and are subject to change, including daily.
Derivative Exposure
Long
Credit Risk0.9
%
Interest Rate Risk50.7
%
Short
Credit Risk2.2
%
Foreign Exchange Risk0.4
%
Interest Rate Risk70.8
%
Asset Cat
eg
ories
Graphical Representation - Allocation 1 Chart
Credit Quality
Graphical Representation - Allocation 2 Chart
Credit Quality Explanation [Text Block] Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a security is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is applied to those bonds that would otherwise be not rated. When a bond is not rated by any rating agency, it is designated as “Not rated.”
Credit
quality ratings assigned by a rating agency are subjective opinions, not statements of fact, and are subject to change, including daily.
Updated Prospectus Web Address columbiathreadneedleus.com/investment-products/mutual-funds