The Fund pays transaction costs 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 fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 28.13% of the average value of its portfolio.

Portfolio Turnover, Rate

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28.13%

Expense Example [Heading]

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Example

Expense Example Narrative [Text Block]

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This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.

This example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

Strategy [Heading]

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Principal Investment Strategies

Strategy Narrative [Text Block]

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The Fund invests primarily in equity securities of mid and large capitalization companies. Under normal circumstances, the Fund invests (except when maintaining a temporary defensive position) 80% of the value of its net assets in equity securities. If the Fund changes this investment policy, it will notify shareholders in writing at least 60 days in advance of the change. Equity securities include common and preferred stock; rights or warrants to purchase common or preferred stock; securities convertible into common or preferred stock such as convertible preferred stock, bonds or debentures; American Depository Receipts (ADRs); and other securities with equity characteristics. The portfolio manager uses a highly focused approach which seeks to achieve superior long-term returns over a full market cycle by owning shares of companies that he believes to have strong and enduring business models and inherent advantages over their competitors.

Portfolio securities may be sold when the company fails to meet expectations, there is deterioration of underlying fundamentals, the portfolio manager concludes that the intermediate and long-term prospects for the company are poor, the portfolio manager determines to take advantage of a better investment opportunity, or, in the portfolio manager's opinion, the security becomes fully valued or the security becomes too large a position in the Fund or the individual security has reached its sell target.

Risk [Heading]

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Principal Risks

Risk Narrative [Text Block]

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Since the Fund holds securities with fluctuating market prices, the value of the Fund's shares will vary as its portfolio securities increase or decrease in value. Therefore, the value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund.

The principal risks affecting the Fund that can cause a decline in value are:

•

equity risk: the risk that stocks and other equity securities generally fluctuate in value more than bonds and may decline in value over short or extended periods based on changes in a company's financial condition and in overall market, economic and political conditions.

•

price volatility risk: the risk that the value of the Fund's investment portfolio will change as the prices of its investments go up or down.

•

liquidity risk: the risk that there may be no willing buyer of the Fund's portfolio securities and the Fund may have to sell those securities at a lower price or may not be able to sell the securities at all, each of which would have a negative effect on performance.

•

market risk: the risk that returns from the securities in which the Fund invests will underperform returns from the general securities markets or other types of securities.

•

securities selection risk: the risk that the securities held by the Fund will underperform other funds investing in the same asset class or benchmarks that are representative of the asset class because of the portfolio manager's choice of securities.

•

portfolio management risk: the risk that an investment strategy may fail to produce the intended results.

•

issuer risk: the risk that the value of a security may decline for reasons directly related to the issuer such as management performance, financial leverage and reduced demand for the issuer's goods or services.

•

investment style risk: the risk that the particular style or set of styles that the investment advisor primarily uses may be out of favor or may not produce the best results over short or longer time periods and may increase the volatility of the Fund's share price.

•

globalization risk: the risk that the growing inter-relationship of all global economies and financial markets has increased the effect of conditions in one country or region on issuers of securities in a different country or region.

•

foreign investing risk: the risk that Fund shares will fluctuate with market conditions, currencies and the political climates where investments are made.

Please see "Principal Risks and Risk Definitions" for a more detailed description of the risks of investing in the Fund.

Your investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency entity or person.

Risk Lose Money [Text]

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You can lose money by investing in the Fund.

Risk Not Insured Depository Institution [Text]

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Your investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency entity or person.

Bar Chart and Performance Table [Heading]

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Investment Results

Performance Narrative [Text Block]

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The bar chart below shows how the Fund's investment results have varied from year to year and the table shows how the Fund's average annual returns for various periods compare with a broad measure of market performance. This information provides some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year. The bar chart shows performance of the Fund's Class I shares. Class N performance would be lower than Class I performance because of the lower expenses paid by Class I shares. Past results (before and after taxes) are not predictive of future results. Updated information on the Fund's investment results can be obtained by visiting tcwfunds.com.

Performance Information Illustrates Variability of Returns [Text]

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Performance Availability Website Address [Text]

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tcwfunds.com

Performance Past Does Not Indicate Future [Text]

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Past results (before and after taxes) are not predictive of future results.

Bar Chart [Heading]

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Calendar Year Total Returns

For Class I Shares

Bar Chart Closing [Text Block]

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Highest/Lowest quarterly results during this period were:


Highest	20.07%	(quarter ended 6/30/2003)
Lowest	-21.93%	(quarter ended 6/30/2002)

Performance Table Heading

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Average Annual Total Returns

(For the period ended December 31, 2011)

Performance Table Uses Highest Federal Rate

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After-tax returns are calculated using the highest individual federal income tax rates in effect each year and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

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Your actual after-tax returns depend on your individual tax situation and likely will differ from the results shown above, and after-tax returns shown are not relevant if you hold your Fund shares through a tax-deferred arrangement, such as a 401(k) plan or individual retirement account (IRA).

Performance Table Narrative

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After-tax returns are calculated using the highest individual federal income tax rates in effect each year and do not reflect the impact of state and local taxes. Your actual after-tax returns depend on your individual tax situation and likely will differ from the results shown above, and after-tax returns shown are not relevant if you hold your Fund shares through a tax-deferred arrangement, such as a 401(k) plan or individual retirement account (IRA).

TCW Select Equities Fund | Russell 1000 Growth Index

Risk/Return:

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1 Year

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2.64%

^[1]

5 Years

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2.50%

^[1]

10 Years

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2.60%

^[1]

[1]	The Russell 1000® Growth Index measures the performance of those Russell 1000 companies with higher price-to-book ratios and higher forecasted growth values.