Shareholder Report
|
6 Months Ended |
|
Apr. 30, 2026
USD ($)
Holding
|
|---|
| Shareholder Report [Line Items] |
|
|
| Document Type |
N-CSRS
|
|
| Amendment Flag |
false
|
|
| Registrant Name |
Capital Income Builder
|
|
| Entity Central Index Key |
0000811968
|
|
| Entity Investment Company Type |
N-1A
|
|
| Document Period End Date |
Apr. 30, 2026
|
|
| Capital Income Builder - Class A |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class A
|
|
| Trading Symbol |
CAIBX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-A. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-A
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class A | $ 30 | 0.57 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 30
|
|
| Expense Ratio, Percent |
0.57%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets) |
|
| Capital Income Builder - Class C |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class C
|
|
| Trading Symbol |
CIBCX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-C. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-C
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class C | $ 68 | 1.32 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 68
|
|
| Expense Ratio, Percent |
1.32%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class T |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class T
|
|
| Trading Symbol |
TCIBX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class T | $ 16 | 0.31 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 16
|
|
| Expense Ratio, Percent |
0.31%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class F-1 |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class F-1
|
|
| Trading Symbol |
CIBFX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-F1. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-F1
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class F-1 | $ 33 | 0.64 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 33
|
|
| Expense Ratio, Percent |
0.64%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - F2 |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class F-2
|
|
| Trading Symbol |
CAIFX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-F2. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-F2
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class F-2 | $ 19 | 0.37 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 19
|
|
| Expense Ratio, Percent |
0.37%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class F-3 |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class F-3
|
|
| Trading Symbol |
CFIHX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-F3. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-F3
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class F-3 | $ 14 | 0.26 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 14
|
|
| Expense Ratio, Percent |
0.26%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class 529-A |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class 529-A
|
|
| Trading Symbol |
CIRAX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-529A. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-529A
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class 529-A | $ 31 | 0.60 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 31
|
|
| Expense Ratio, Percent |
0.60%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class 529-C |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class 529-C
|
|
| Trading Symbol |
CIRCX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-529C. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-529C
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class 529-C | $ 71 | 1.37 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 71
|
|
| Expense Ratio, Percent |
1.37%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class 529-E |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class 529-E
|
|
| Trading Symbol |
CIREX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-529E. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-529E
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class 529-E | $ 44 | 0.84 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 44
|
|
| Expense Ratio, Percent |
0.84%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class 529-T |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class 529-T
|
|
| Trading Symbol |
TCBBX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class 529-T | $ 19 | 0.37 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 19
|
|
| Expense Ratio, Percent |
0.37%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class 529-F-1 |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class 529-F-1
|
|
| Trading Symbol |
CIRFX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-529F1. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-529F1
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class 529-F-1 | $ 23 | 0.44 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 23
|
|
| Expense Ratio, Percent |
0.44%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class 529-F-2 |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class 529-F-2
|
|
| Trading Symbol |
FBCIX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-529F2. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-529F2
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class 529-F-2 | $ 18 | 0.35 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 18
|
|
| Expense Ratio, Percent |
0.35%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class 529-F-3 |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class 529-F-3
|
|
| Trading Symbol |
FWCBX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-529F3. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-529F3
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class 529-F-3 | $ 16 | 0.31 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 16
|
|
| Expense Ratio, Percent |
0.31%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class R-1 |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class R-1
|
|
| Trading Symbol |
RIRAX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R1. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-R1
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class R-1 | $ 70 | 1.35 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 70
|
|
| Expense Ratio, Percent |
1.35%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class R-2 |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class R-2
|
|
| Trading Symbol |
RIRBX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R2. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-R2
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class R-2 | $ 70 | 1.36 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 70
|
|
| Expense Ratio, Percent |
1.36%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class R-2E |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class R-2E
|
|
| Trading Symbol |
RCEEX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R2E. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-R2E
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class R-2E | $ 55 | 1.06 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 55
|
|
| Expense Ratio, Percent |
1.06%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class R-3 |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class R-3
|
|
| Trading Symbol |
RIRCX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R3. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-R3
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class R-3 | $ 47 | 0.91 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 47
|
|
| Expense Ratio, Percent |
0.91%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class R-4 |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class R-4
|
|
| Trading Symbol |
RIREX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R4. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-R4
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class R-4 | $ 32 | 0.61 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 32
|
|
| Expense Ratio, Percent |
0.61%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class R-5E |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class R-5E
|
|
| Trading Symbol |
RIRHX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R5E. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-R5E
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class R-5E | $ 21 | 0.41 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 21
|
|
| Expense Ratio, Percent |
0.41%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class R-5 |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class R-5
|
|
| Trading Symbol |
RIRFX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R5. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-R5
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class R-5 | $ 16 | 0.31 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 16
|
|
| Expense Ratio, Percent |
0.31%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
| Capital Income Builder - Class R-6 |
|
|
| Shareholder Report [Line Items] |
|
|
| Fund Name |
Capital Income Builder®
|
|
| Class Name |
Class R-6
|
|
| Trading Symbol |
RIRGX
|
|
| Annual or Semi-Annual Statement [Text Block] |
This semi-annual shareholder report contains important information about Capital Income Builder (the "fund") for the period from November 1, 2025 to April 30, 2026.
|
|
| Shareholder Report Annual or Semi-Annual |
semi-annual shareholder report
|
|
| Additional Information [Text Block] |
You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R6. You can also request this information by contacting us at (800) 421-4225.
|
|
| Additional Information Phone Number |
(800) 421-4225
|
|
| Additional Information Website |
capitalgroup.com/mutual-fund-literature-R6
|
|
| Expenses [Text Block] |
What were the fund costs for the last six months? (based on a hypothetical $10,000 investment) | Share class | Costs of a $10,000 investment | Costs paid as a percentage of a $10,000 investment | | Class R-6 | $ 14 | 0.26 % * |
*Annualized.
|
|
| Expenses Paid, Amount |
$ 14
|
|
| Expense Ratio, Percent |
0.26%
|
[1] |
| Net Assets |
$ 126,774,000,000
|
|
| Holdings Count | Holding |
2,714
|
|
| Investment Company, Portfolio Turnover |
32.00%
|
|
| Additional Fund Statistics [Text Block] |
Key fund statistics | Fund net assets (in millions) | $ 126,774 | | Total number of portfolio holdings | 2,714 | Portfolio turnover rate including
mortgage dollar roll transactions | 32 % | | Portfolio turnover rate excluding mortgage dollar roll transactions | 26 % |
|
|
| Holdings [Text Block] |
Portfolio holdings by sector (percent of net assets)  *Includes derivatives.
|
|
|
|
