Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY CHARLES STREET TRUST

Prospectus Date

rr_ProspectusDate

Dec. 30, 2014

A T B C | Fidelity Global Balanced Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary

Fund/Class:
Fidelity^® Global Balanced Fund/Fidelity Advisor^® Global Balanced Fund A, T, B, C

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks income and capital growth consistent with reasonable risk.

Expense [Heading]

rr_ExpenseHeading

Fee Table

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity funds. More information about these and other discounts is available from your investment professional and in the Fund Distribution section beginning on page (Click Here) of the prospectus.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

Shareholder fees
(fees paid directly from your investment)

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual operating expenses
(expenses that you pay each year as a % of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 157% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

157.00%

Expense Breakpoint Discounts [Text]

rr_ExpenseBreakpointDiscounts

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity funds.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

50,000

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

Sell All Shares

Expense Example, No Redemption, By Year, Caption [Text]

rr_ExpenseExampleNoRedemptionByYearCaption

Hold Shares

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Investing in equity and debt securities, including lower-quality debt securities, issued throughout the world.
• Investing at least 25% of total assets in fixed-income senior securities (including debt securities and preferred stock).
• Allocating investments across different countries and regions.
• Analyzing an issuer using fundamental factors (e.g., financial condition, earnings outlook, and strategy) and evaluating each security's current price relative to estimated long-term value to select investments.
• Investing in Fidelity's central funds (specialized investment vehicles used by Fidelity funds to invest in particular security types or investment disciplines).

Risk [Heading]

rr_RiskHeading

Principal Investment Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.
• Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease.
• Foreign Exposure. Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market. Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile. Foreign exchange rates also can be extremely volatile.
• Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) and certain types of other securities involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities and certain types of other securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

You could lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Bar Chart and Performance Table [Heading]

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Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and a hypothetical composite of market indexes over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the Additional Index Information section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.advisor.fidelity.com for updated return information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and a hypothetical composite of market indexes over various periods of time.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

www.advisor.fidelity.com

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

Past performance (before and after taxes) is not an indication of future performance.

Bar Chart [Heading]

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Year-by-Year Returns

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.

Calendar Years

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart for Class A:	Returns	Quarter ended
Highest Quarter Return	12.74%	September 30, 2010
Lowest Quarter Return	-10.72%	September 30, 2011
Year-to-Date Return	-0.08%	September 30, 2014

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Returns

Performance Table Does Reflect Sales Loads

rr_PerformanceTableDoesReflectSalesLoads

Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges.

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary.

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement. Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended
December 31, 2013

A T B C | Fidelity Global Balanced Fund | Class A

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

5.75%

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

^[1]

Redemption fee on shares held less than 30 days (as a % of amount redeemed)

rr_RedemptionFeeOverRedemption

1.00%

Management fee

rr_ManagementFeesOverAssets

0.70%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other expenses

rr_OtherExpensesOverAssets

0.33%

Total annual operating expenses

rr_ExpensesOverAssets

1.28%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Class A and Class T purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class T purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

1 year

rr_ExpenseExampleYear01

698

3 years

rr_ExpenseExampleYear03

958

5 years

rr_ExpenseExampleYear05

1,237

10 years

rr_ExpenseExampleYear10

2,031

1 year

rr_ExpenseExampleNoRedemptionYear01

698

3 years

rr_ExpenseExampleNoRedemptionYear03

958

5 years

rr_ExpenseExampleNoRedemptionYear05

1,237

10 years

rr_ExpenseExampleNoRedemptionYear10

2,031

2010

rr_AnnualReturn2010

12.10%

2011

rr_AnnualReturn2011

(2.80%)

2012

rr_AnnualReturn2012

11.64%

2013

rr_AnnualReturn2013

15.25%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2014

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(0.08%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

12.74%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(10.72%)

A T B C | Fidelity Global Balanced Fund | Class T

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

3.50%

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

^[1]

Redemption fee on shares held less than 30 days (as a % of amount redeemed)

rr_RedemptionFeeOverRedemption

1.00%

Management fee

rr_ManagementFeesOverAssets

0.70%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other expenses

rr_OtherExpensesOverAssets

0.35%

Total annual operating expenses

rr_ExpensesOverAssets

1.55%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Class A and Class T purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class T purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

1 year

rr_ExpenseExampleYear01

502

3 years

rr_ExpenseExampleYear03

822

5 years

rr_ExpenseExampleYear05

1,165

10 years

rr_ExpenseExampleYear10

2,131

1 year

rr_ExpenseExampleNoRedemptionYear01

502

3 years

rr_ExpenseExampleNoRedemptionYear03

822

5 years

rr_ExpenseExampleNoRedemptionYear05

1,165

10 years

rr_ExpenseExampleNoRedemptionYear10

2,131

A T B C | Fidelity Global Balanced Fund | Class B

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

5.00%

^[2]

Redemption fee on shares held less than 30 days (as a % of amount redeemed)

rr_RedemptionFeeOverRedemption

1.00%

Management fee

rr_ManagementFeesOverAssets

0.70%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other expenses

rr_OtherExpensesOverAssets

0.37%

Total annual operating expenses

rr_ExpensesOverAssets

2.07%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Declines over 6 years from 5.00% to 0%.

1 year

rr_ExpenseExampleYear01

710

3 years

rr_ExpenseExampleYear03

949

5 years

rr_ExpenseExampleYear05

1,314

10 years

rr_ExpenseExampleYear10

2,103

1 year

rr_ExpenseExampleNoRedemptionYear01

210

3 years

rr_ExpenseExampleNoRedemptionYear03

649

5 years

rr_ExpenseExampleNoRedemptionYear05

1,114

10 years

rr_ExpenseExampleNoRedemptionYear10

2,103

A T B C | Fidelity Global Balanced Fund | Class C

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

1.00%

^[3]

Redemption fee on shares held less than 30 days (as a % of amount redeemed)

rr_RedemptionFeeOverRedemption

1.00%

Management fee

rr_ManagementFeesOverAssets

0.70%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other expenses

rr_OtherExpensesOverAssets

0.38%

Total annual operating expenses

rr_ExpensesOverAssets

2.08%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

On Class C shares redeemed less than one year after purchase.

1 year

rr_ExpenseExampleYear01

311

3 years

rr_ExpenseExampleYear03

652

5 years

rr_ExpenseExampleYear05

1,119

10 years

rr_ExpenseExampleYear10

2,410

1 year

rr_ExpenseExampleNoRedemptionYear01

211

3 years

rr_ExpenseExampleNoRedemptionYear03

652

5 years

rr_ExpenseExampleNoRedemptionYear05

1,119

10 years

rr_ExpenseExampleNoRedemptionYear10

2,410

A T B C | Fidelity Global Balanced Fund | Return Before Taxes | Class A

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Class A - Return Before Taxes

Past 1 year

rr_AverageAnnualReturnYear01

8.63%

Life of class

rr_AverageAnnualReturnSinceInception

12.65%

^[4]

Inception Date

rr_AverageAnnualReturnInceptionDate

Feb. 19, 2009

A T B C | Fidelity Global Balanced Fund | Return Before Taxes | Class T

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Class T - Return Before Taxes

Past 1 year

rr_AverageAnnualReturnYear01

10.92%

Life of class

rr_AverageAnnualReturnSinceInception

12.93%

^[4]

Inception Date

rr_AverageAnnualReturnInceptionDate

Feb. 19, 2009

A T B C | Fidelity Global Balanced Fund | Return Before Taxes | Class B

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Class B - Return Before Taxes

Past 1 year

rr_AverageAnnualReturnYear01

9.30%

Life of class

rr_AverageAnnualReturnSinceInception

12.89%

^[4]

Inception Date

rr_AverageAnnualReturnInceptionDate

Feb. 19, 2009

A T B C | Fidelity Global Balanced Fund | Return Before Taxes | Class C

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Class C - Return Before Taxes

Past 1 year

rr_AverageAnnualReturnYear01

13.30%

Life of class

rr_AverageAnnualReturnSinceInception

13.16%

^[4]

Inception Date

rr_AverageAnnualReturnInceptionDate

Feb. 19, 2009

A T B C | Fidelity Global Balanced Fund | Return After Taxes on Distributions | Class A

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Class A - Return After Taxes on Distributions

Past 1 year

rr_AverageAnnualReturnYear01

5.94%

Life of class

rr_AverageAnnualReturnSinceInception

11.79%

^[4]

Inception Date

rr_AverageAnnualReturnInceptionDate

Feb. 19, 2009

A T B C | Fidelity Global Balanced Fund | Return After Taxes on Distributions and Sale of Fund Shares | Class A

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Class A - Return After Taxes on Distributions and Sale of Fund Shares

Past 1 year

rr_AverageAnnualReturnYear01

6.04%

Life of class

rr_AverageAnnualReturnSinceInception

9.99%

^[4]

Inception Date

rr_AverageAnnualReturnInceptionDate

Feb. 19, 2009

A T B C | Fidelity Global Balanced Fund | MSCI World Index (reflects no deduction for fees or expenses)

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

MSCI World Index

Past 1 year

rr_AverageAnnualReturnYear01

27.18%

Life of class

rr_AverageAnnualReturnSinceInception

19.54%

^[4]

Inception Date

rr_AverageAnnualReturnInceptionDate

Feb. 19, 2009

A T B C | Fidelity Global Balanced Fund | Fidelity Global Balanced Composite Index℠ (reflects no deduction for fees or expenses)

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Fidelity Global Balanced Composite Index℠

Past 1 year

rr_AverageAnnualReturnYear01

13.81%

Life of class

rr_AverageAnnualReturnSinceInception

13.22%

^[4]

Inception Date

rr_AverageAnnualReturnInceptionDate

Feb. 19, 2009

[1] Class A and Class T purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class T purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

[2] Declines over 6 years from 5.00% to 0%.

[3] On Class C shares redeemed less than one year after purchase.

[4] From February 19, 2009.