v3.25.2
Investment Risks - Harbor Alpha Layering ETF
Jul. 15, 2025
Equity Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Equity Risk: The values of equity or equity-related securities may decline due to general market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities.
Large Cap Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Large Cap Risk: Large cap stocks may fall out of favor relative to small or mid cap stocks, which may cause the Fund to underperform other equity funds that focus on small or mid cap stocks. Large cap companies may be less able than smaller cap companies to adapt to changing market conditions and may be more mature and subject to more limited growth potential than smaller cap companies.
Derivatives Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Derivatives Risk: The value of derivative instruments, such as futures contracts,  held by the Fund may not change in the manner expected by the Subadvisor which could result in disproportionately large losses to the Fund. Derivatives may also be more volatile than other instruments and may create a risk of loss greater than the amount invested. In addition, certain derivatives may be difficult to value and may be illiquid.
Short Position Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Short Position Risk: Taking short positions involves leverage of the Fund’s assets and presents various risks. If the value of the underlying instrument or market in which the Fund has taken a short position increases, then the Fund will incur a loss equal to the increase in value from the time that the short position was entered into plus any related interest payments or other fees. Taking short positions involves the risk that losses may be disproportionate, may exceed the amount invested and may be unlimited.
Leveraging Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Leveraging Risk: The Fund’s use of certain investments, such as derivative instruments, including futures contracts, and certain other transactions can give rise to leverage within the Fund’s portfolio, which could cause the Fund’s returns to be more volatile than if leverage had not been used.
Large Shareholder Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Large Shareholder Risk: Certain large shareholders, including Authorized Participants (“APs”) may from time to time own a substantial amount of the Fund’s shares. There is no requirement that these shareholders maintain their investment in the Fund. There is a risk that such large shareholders or that the Fund’s shareholders generally may redeem all or a substantial portion of their investments in the Fund in a short period of time, which could have a significant negative impact on the Fund’s NAV, liquidity, and brokerage costs. Large redemptions could also result in tax consequences to shareholders and impact the Fund’s ability to implement its investment strategy. In addition, transactions by large shareholders may account for a large percentage of the trading volume on the listing exchange and may, therefore, have a material upward or downward effect on the market price of the shares.
Premium Discount Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Premium/Discount Risk: The market price of the Fund’s shares will generally fluctuate in accordance with changes in the Fund’s net asset value as well as the relative supply of and demand for shares on the Exchange. The Advisor cannot predict whether shares will trade below, at or above their net asset value because the shares trade on the Exchange at market prices and not at net asset value. Price differences may be due, in large part, to the fact that supply and demand forces at work in the secondary trading market for shares will be closely related, but not identical, to the same forces influencing the prices of the holdings of the Fund trading individually or in the aggregate at any point in time. This may result in the Fund’s shares trading significantly above (premium) or below (discount) the Fund’s net asset value, which will be reflected in the intraday bid/ask spreads and/or the closing price of shares as compared to net asset value. During stressed market conditions, the market for the Fund’s shares may become less liquid in response to deteriorating liquidity in the market for the Fund’s underlying portfolio holdings, which could in turn lead to differences between the market price of the Fund’s shares and their net asset value.
Market Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Market Risk: Securities markets are volatile and can decline significantly in response to adverse market, economic, political, regulatory or other developments, which may lower the value of securities held by the Fund, sometimes rapidly or unpredictably. Events such as war, acts of terrorism, social unrest, natural disasters, recessions, inflation, rapid interest rate changes, supply chain disruptions, sanctions, the spread of infectious illness or other public health threats could also significantly impact the Fund and its investments.
Model Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Model Risk: There are limitations inherent in every quantitative model. The value of securities selected using quantitative analysis can react differently to issuer, political, market, and economic developments than the market as a whole or securities selected using only fundamental analysis. The factors used in quantitative analysis and the weight placed on those factors may not be predictive of a security’s value. In addition, historical trends in data may not be predictive going forward. The strategies and techniques employed in a quantitative model cannot fully match the complexity of the financial markets and therefore sudden unanticipated changes in underlying market conditions can significantly impact their performance. The effectiveness of the given strategy or technique may deteriorate in an unpredictable fashion for any number of reasons including, but not limited to, an increase in the amount of assets managed or the use of similar strategies or techniques by other market participants and/or market dynamic shifts over time. In addition, factors that affect a security’s value can change over time, and these changes may not be reflected in the quantitative model. Any model may contain flaws the existence and effect of which may be discovered only after the fact or not at all. There can be no assurances that the strategies pursued or the techniques implemented in the quantitative model will be profitable, and various market conditions may be materially less favorable to certain strategies than others. Even in the absence of flaws, a model may not perform as anticipated.
Authorized Participant Concentration Trading Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Authorized Participant Concentration/Trading Risk: Only APs may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of institutions that may act as APs and such APs have no obligation to submit creation or redemption orders. Consequently, there is no assurance that APs will establish or maintain an active trading market for the shares. This risk may be heightened to the extent that securities held by the Fund are traded outside a collateralized settlement system. In that case, APs may be required to post collateral on certain trades on an agency basis (i.e., on behalf of other market participants), which only a limited number of APs may be able to do. In addition, to the extent that APs exit the business or are unable to proceed with creation and/or redemption orders with respect to the Fund and no other AP is able to step forward to create or redeem Creation Units (as defined below), this may result in a significantly diminished trading market for shares, and shares may be more likely to trade at a premium or discount to the Fund’s net asset value and to face trading halts and/or delisting. This risk may be heightened during periods of volatility or market disruptions.
Cash Transactions Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Cash Transactions Risk: The Fund may effect some or all of its creations and redemptions for cash rather than in-kind. As a result, an investment in the Fund may be less tax-efficient than an investment in an ETF that effects all of its creations and redemptions in-kind. Because the Fund may effect redemptions for cash, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. A sale of portfolio securities may result in capital gains or losses and may also result in higher brokerage costs. To the extent costs are not offset by transaction fees charged by the Fund to APs, the costs of cash transactions will be borne by the Fund.
Commodity Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Commodity Risk: The Fund has exposure to commodities through investments (either directly or through the Subsidiary) in commodity-linked derivative instruments. Commodity prices are generally affected by, among other factors, the cost of producing, transporting and storing commodities, changes in consumer or commercial demand for commodities, the hedging and trading strategies of producers and consumers of commodities, speculative trading in commodities by commodity pools and other market participants, disruptions in commodity supply, weather, political and other global events, global economic factors and government intervention in or regulation of the commodity or commodity futures markets.
Commodity-Linked Derivatives Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Commodity-Linked Derivatives Risk: The Fund’s investments in commodity-linked derivative instruments (either directly or through the Subsidiary) may subject the Fund to significantly greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by prevailing spot prices (the price at which a commodity can be bought or sold for immediate delivery) for the underlying commodity, supply and demand, market activity, liquidity, economic, financial, political regulatory, geographical, biological or judicial events, and the general interest rate environment. Commodity-linked derivatives are subject to the risk that the counterparty to the transaction, the exchange or trading facility on which they trade, or the applicable clearing house may default or otherwise fail to perform. The Fund will incur certain costs as a result of its use of derivatives and is required to post margin in respect to certain of its holdings in derivatives. Costs incurred by the Fund as a result of its use of derivatives will ultimately be borne by shareholders. The Fund’s use of commodity-linked derivatives will have a leveraging effect on the Fund’s portfolio. Leverage generally magnifies the effect of a change in the value of an asset and creates a risk of loss of value on a larger pool of assets than the Fund otherwise would have had. The Fund’s exposure to leverage can substantially increase the adverse impact to which the Fund’s investment portfolio may be subject and make the Fund more volatile.
Counterparty Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Counterparty Risk: A counterparty may be unwilling or unable to meet its contractual obligations. If the counterparty or its affiliate becomes insolvent, bankrupt or defaults ion its payment obligations to the Fund, the value of an investment held by the Fund may decline. The Fund may also not be able to exercise remedies, such as the termination of transactions, netting of obligations and realization on collateral if such remedies are stayed or eliminated under special resolutions adopted in the United States or other jurisdictions. In addition, the Fund may enter into swap agreements with a limited number of counterparties, which may increase the Fund’s exposure to counterparty credit risk. Counterparties may be less willing to enter into transactions in stressed or volatile market conditions or may alter the terms they are willing to accept in such conditions. Further, there is a risk that no suitable counterparties will be willing to enter into, or continue to enter into, transactions with the Fund, which may cause the Fund not to be able to achieve its investment objective or to change its investment objective.
Currency Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Currency Risk: The risk that foreign currencies will decline in value relative to the U.S. dollar and affect the Fund’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies.
Emerging Market Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Emerging Market Risk: Because the Fund may invest in securities of emerging market issuers, an investment in the Fund may be subject to special risks in addition to those of U.S. securities. These risks include heightened political and economic risks, greater volatility, currency fluctuations, higher transaction costs, delayed settlement, possible foreign controls on investment, possible sanctions by governmental bodies of other countries and less stringent investor protection and disclosure standards of foreign markets. Foreign securities are sometimes less liquid and harder to value than securities of U.S. issuers. The securities markets of many foreign countries are relatively small, with a limited number of companies representing a small number of industries. If foreign securities are denominated and traded in a foreign currency, the value of the Fund’s foreign holdings can be affected by currency exchange rates and exchange control regulations. The Fund’s investments in foreign securities may also be subject to foreign withholding taxes.Foreign securities risks are more significant in emerging market countries. These countries may have relatively unstable governments and less-established market economies than developed countries. Emerging markets may face greater social, economic, regulatory and political uncertainties. These risks make emerging market securities more volatile and less liquid than securities issued in more developed countries. Securities exchanges in emerging markets may suspend listed securities from trading for substantially longer periods of time than exchanges in developed markets, including for periods of a year or longer. If the Fund is holding a suspended security, that security would become completely illiquid as the Fund would not be able to dispose of the security until the suspension is lifted. In such instances, it can also be difficult to determine an appropriate valuation for the security because of a lack of trading and uncertainty as to when trading may resume.Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market.
Foreign Securities Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Foreign Securities Risk: Because the Fund may invest in securities of foreign issuers, an investment in the Fund is subject to special risks in addition to those of U.S. securities. These risks include heightened political and economic risks, greater volatility, currency fluctuations, higher transaction costs, delayed settlement, possible foreign controls on investment, possible sanctions by governmental bodies of other countries and less stringent investor protection and disclosure standards of foreign markets. Foreign securities are sometimes less liquid and harder to value than securities of U.S. issuers. These risks are more significant for issuers in emerging market countries. Foreign market trading hours and holiday schedules may limit the Fund’s ability to buy and sell securities. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market.
High Portfolio Turnover Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] High Portfolio Turnover Risk: Higher portfolio turnover may adversely affect Fund performance by increasing Fund transaction costs and may lead to the realization and distribution to shareholders of higher capital gains, which may increase a shareholder’s tax liability.
Investment in Other Investment Companies Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Investment in Other Investment Companies Risk: Investments in other investment companies (including money market funds) are subject to market and selection risk. In addition, if the Fund acquires shares of investment companies, shareholders bear both their proportionate share of expenses in the Fund and, indirectly, the expenses of the investment companies. In addition to these risks, a sector ETF may fail to accurately track the market segment or index that underlies its investment objective and the market price of the underlying ETF’s shares may trade at a premium or a discount to their net asset value.
Interest Rate Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Interest Rate Risk: As interest rates rise, the values of fixed income securities held by the Fund are likely to decrease and reduce the value of the Fund’s portfolio. Securities with longer durations tend to be more sensitive to changes in interest rates and are usually more volatile than securities with shorter durations. For example, a 5 year average duration generally means the price of a fixed income security will decrease in value by 5% if interest rates rise by 1%. Rising interest rates may lead to increased redemptions, increased volatility and decreased liquidity in the fixed income markets, making it more difficult for the Fund to sell its fixed income securities when the Subadvisor may wish to sell or must sell to meet redemptions. During periods when interest rates are low or there are negative interest rates, the Fund’s yield (and total return) also may be low or the Fund may be unable to maintain positive returns or minimize the volatility of the Fund’s net asset value per share. Changing interest rates may have unpredictable effects on the markets, may result in heightened market volatility and may detract from Fund performance. In addition, changes in monetary policy may exacerbate the risks associated with changing interest rates.
Issuer Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Issuer Risk: An adverse event affecting a particular issuer in which the Fund is invested, such as an unfavorable earnings report, may depress the value of that issuer’s securities, sometimes rapidly or unpredictably.
New Fund Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] New Fund Risk: There can be no assurance that the Fund will grow to or maintain an economically viable size, in which case the Board of Trustees may determine to liquidate the Fund. The Board of Trustees may liquidate the Fund at any time in accordance with the Declaration of Trust and governing law. As a result, the timing of the Fund’s liquidation may not be favorable.
Sector Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Sector Risk: Because the Fund may, from time to time, be more heavily invested in particular sectors, the value of its shares may be especially sensitive to factors and economic risks that specifically affect those sectors. As a result, the Fund’s share price may fluctuate more widely than the value of shares of a mutual fund that invests in a broader range of sectors.
Selection Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Selection Risk: The Subadvisor’s judgment about the attractiveness, value and growth potential of a particular security may be incorrect, which may cause the Fund to underperform. Additionally, the Subadvisor potentially will be prevented from executing investment decisions at an advantageous time or price as a result of domestic or global market disruptions, particularly disruptions causing heightened market volatility and reduced market liquidity, as well as increased or changing regulations.  Thus, investments that the Subadvisor believes represent an attractive opportunity or in which the Fund seeks to obtain exposure may be unavailable entirely or in the specific quantities or prices sought by the Subadvisor and the Fund may need to forgo the investment at the time.
Short Sales Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Short Sales Risk: If the price of securities sold short increases, the Fund would be required to pay more to replace the borrowed securities than the Fund received on the sale of the securities. Because there is theoretically no limit to the amount of the increase in price of the borrowed securities, the Fund’s risk of loss on a short sale is potentially unlimited if the Fund misperceived or misjudged the relevant securities’ value. Short sales involve what is referred to as counterparty risk or the risk that a loss may be sustained as a result of the failure or inability of the broker-dealer through which the Fund made the short sale (the “counterparty”) to comply with the terms of the contract.
Subsidiary Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Subsidiary Risk: By investing in the Subsidiary, the Fund is indirectly exposed to the risks associated with the Subsidiary’s investments. The derivatives and other investments held by the Subsidiary are the same as those that are permitted to be held by the Fund and are subject to the same risks that apply to similar investments if held directly by the Fund. The Subsidiary is not registered under the Investment Company Act of 1940 (the “Investment Company Act”), and, unless otherwise noted in this prospectus, is not subject to all of the investor protections of the Investment Company Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Fund and/or the Subsidiary to operate as described in this Prospectus and the Statement of Additional Information and could adversely affect the Fund.
Tax Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Tax Risk: The ability of the Fund to gain commodity exposure as contemplated may be adversely affected by future legislation, regulatory developments, interpretive guidance or other actions by the Internal Revenue Service (“IRS”) or the U.S. Department of the Treasury.
U.S. Treasury Obligations Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] U.S. Treasury Obligations Risk: U.S. Treasury obligations may differ from other securities in their interest rates, maturities, times of issuance and other characteristics. Similar to other issuers, changes to the financial condition or credit rating of the U.S. government may cause the value of the Fund’s exposure to U.S. Treasury obligations to decline.
Risk Lose Money [Member]  
Prospectus [Line Items]  
Risk [Text Block] This means that you could lose money on your investment in the Fund or the Fund may not perform as well as other investment options.
Risk Nondiversified Status [Member]  
Prospectus [Line Items]  
Risk [Text Block] Non-Diversification Risk: Because the Fund is non-diversified and may invest a greater percentage of its assets in securities of a single issuer, and/or invest in a relatively small number of issuers, it is more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio.