0000836423 2012-11-21 2012-11-21 0000836423 oppenheimer:S000006965Member oppenheimer:AAAAMember 2012-11-21 2012-11-21 0000836423 oppenheimer:S000006965Member oppenheimer:C000019001Member oppenheimer:AAAAMember 2012-11-21 2012-11-21 0000836423 oppenheimer:S000006965Member oppenheimer:C000019002Member oppenheimer:AAAAMember 2012-11-21 2012-11-21 0000836423 oppenheimer:S000006965Member oppenheimer:C000019003Member oppenheimer:AAAAMember 2012-11-21 2012-11-21 0000836423 oppenheimer:S000006965Member oppenheimer:C000019004Member oppenheimer:AAAAMember 2012-11-21 2012-11-21 xbrli:pure iso4217:USD xbrli:shares iso4217:USD xbrli:shares 485BPOS 2012-07-31 OPPENHEIMER CASH RESERVES 0000836423 false 2012-11-21 2012-11-20 2012-11-21 <div style="display: none">~ http://xbrl.sec.gov/rr/role/RiskReturnDetailData column period compact * row dei_DocumentInformationDocumentAxis compact * row dei_LegalEntityAxis compact * row rr_ProspectusShareClassAxis compact * row rr_PerformanceMeasureAxis compact * row primary compact * ~</div> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b>Investment Objective.</b> The Fund seeks income consistent with stability of principal.</p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b> Fees and Expenses of the Fund.</b> This table describes the fees and expenses that you may pay if you buy and hold or redeem shares of the Fund. You may qualify for sales charge discounts if you (or you and your spouse) invest, or agree to invest in the future, at least $25,000 in certain funds in the Oppenheimer family of funds. More information about these and other discounts is available from your financial professional and in the section "About Your Account" beginning on page 9 of the prospectus, and in the sections "How to Buy Shares" beginning on page 38 and "Appendix A" in the Fund's Statement of Additional Information.</p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b>Shareholder Fees (fees paid directly from your investment) </b> </p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b>Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)</b></p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b>Example.</b> The following Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in a class of shares of the Fund for the time periods indicated. 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 expenses would be as follows: </p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b> If shares are redeemed </b></p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b> If shares are not redeemed </b></p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b>Principal Investment Strategies.</b> The Fund is a money market fund that invests in a variety of money market instruments to seek current income. Money market instruments are short-term, high-quality dollar-denominated debt instruments issued by the U.S. Government, domestic and foreign corporations and financial institutions, and other entities. Money market instruments include bank obligations, repurchase agreements, commercial paper, and other short-term corporate and governmental debt obligations. </p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> To be considered "high-quality," a debt instrument must be rated in one of the two highest credit-quality categories for short-term securities by a nationally recognized statistical rating service or, if a security is unrated, it must be determined by the Fund's investment manager, OppenheimerFunds, Inc. (the "Manager"), under the supervision of the Fund's Board, to be of comparable quality to rated securities in one of those two categories.</p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b>Principal Risks.</b> All investments carry risks to some degree. The Fund's investments are subject to changes in their value from a number of factors. However, the Fund's investments must meet strict standards set by its Board of Trustees and special rules under Federal law for money market funds. Those requirements include maintaining high credit quality, a short average maturity and diversification of the Fund's investments among issuers. Those provisions are designed to help minimize credit risks, to reduce the effects of changes in prevailing interest rates and to reduce the effect on the Fund's portfolio of a default by any one issuer. Since income on short-term securities tends to be lower than income on longer-term debt securities, the Fund's yield will likely be lower than the yield on longer-term fixed-income funds.</p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;">Even so, there are risks that an issuer of an obligation that the Fund holds might have its credit rating downgraded or might default on its obligations, or that interest rates might rise sharply, causing the value of the Fund's investments to fall. Also, there is the risk that the value of your investment could be eroded over time by the effects of inflation, or that poor security selection could cause the Fund to underperform other funds that have a similar objective. If there is an unexpectedly high demand for the redemption of Fund shares, the Fund might need to sell portfolio securities prior to their maturity, possibly at a loss. As a result, there is a risk that the Fund's shares could fall below $1.00 per share.</p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b>Interest Rate Risk.</b> The values of debt securities usually change when prevailing interest rates change. When interest rates fall, the values of already-issued debt securities generally rise. </p><p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> When interest rates rise, the values of already-issued debt securities generally fall. The values of longer-term debt securities usually change more when interest rates change than the values of shorter-term debt securities.</p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b>Credit Risk.</b> Debt securities are also subject to credit risk, which is the risk that the issuer of a security might not make principal or interest payments on the security when they are due. If the issuer fails to pay interest, the Fund's income might be reduced, and if the issuer fails to pay interest or repay principal, the value of the security might fall.</p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b>Fixed-Income Market Risks.</b> Economic and other market developments can adversely affect fixed-income securities markets in the United States, Europe and elsewhere. At times, participants in debt securities markets may develop concerns about the ability of certain issuers of debt securities to make timely principal and interest payments, or they may develop concerns about the ability of financial institutions that make markets in certain debt securities to facilitate an orderly market. Those concerns can cause increased volatility in those debt securities or debt securities markets. Under some circumstances, as was the case during the latter half of 2008 and early 2009, those concerns could cause reduced liquidity in certain debt securities markets. A lack of liquidity or other adverse credit market conditions may hamper the Fund's ability to sell the debt securities in which it invests or to find and purchase suitable debt instruments.</p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b>Who Is the Fund Designed For?</b> The Fund is designed for investors who want to earn income at money market rates while seeking to preserve the value of their investment and maintaining easy access to their investment through checkwriting and wire redemption privileges. The Fund will invest in a variety of money market instruments to seek current income and stability of principal and to try to maintain a stable share price of $1.00. The Fund is not a complete investment program.</p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b> An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it is possible to lose money by investing in the Fund. </b> </p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b>The Fund's Past Performance.</b> The bar chart and table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing the Fund's average annual returns for 1, 5 and 10 year periods. The Fund's past investment performance is not necessarily an indication of how the Fund will perform in the future. More recent performance information is available by calling the toll-free number on the back of this prospectus and on the Fund's website at:</p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <u>https://www.oppenheimerfunds.com/fund/investors/overview/CashReserves</u>.</p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;">During the period shown, the highest return for a calendar quarter was 1.14% (3rd Qtr 2007) and the lowest return for a calendar quarter was 0.00% (most recently in 4th Qtr 2011). For the period from January 1, 2012 through September 30, 2012, the cumulative return before taxes was 0.01%.</p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;">The following table shows the average annual total returns of each class of the Fund's shares before taxes.</p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <b>Average Annual Total Returns for the periods ended December 31, 2011</b></p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;">The Fund's performance reflects income reinvestment and all applicable fees and sales charges.</p> <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;"> <i> The total returns are not the Fund's current yield. The Fund's yield more closely reflects the Fund's current earnings. <b>To obtain the Fund's current 7-day yield information, please call the Transfer Agent toll-free at 1.800.CALL OPP (225.5677).</b></i> </p> <div style="display:none">~http://oppenheimer/role/ShareholderFeesDataAAAA column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_LegalEntityAxis compact oppenheimer_S000006965Member ~</div> 0 0 0 0.05 0 0.01 0 0.01 <div style="display:none">~ http://oppenheimer/role/OperatingExpensesDataAAAA column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_LegalEntityAxis compact oppenheimer_S000006965Member ~</div> 0.0046 0.002 0.0029 0.0095 -0.0064 0.0031 0.0046 0.0075 0.0038 0.0159 -0.0129 0.003 0.0046 0.0075 0.003 0.0151 -0.0121 0.003 0.0046 0.005 0.0031 0.0127 -0.0097 0.003 <div style="display:none">~ http://oppenheimer/role/ExpenseExampleAAAA column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_LegalEntityAxis compact oppenheimer_S000006965Member ~</div> 32 531 131 131 240 678 361 308 465 949 714 607 1113 1456 1710 1457 <div style="display:none">~ http://oppenheimer/role/ExpenseExampleNoRedemptionAAAA column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_LegalEntityAxis compact oppenheimer_S000006965Member ~</div> 32 31 31 31 240 378 361 308 465 749 714 607 1113 1456 1710 1457 <div style="display:none">~ http://oppenheimer/role/BarChartDataAAAA column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_LegalEntityAxis compact oppenheimer_S000006965Member ~</div> 0.0082 0.0028 0.0045 0.0233 0.0421 0.0457 0.0242 0.0014 0.0001 0.0001 <div style="display:none">~ http://oppenheimer/role/PerformanceTableDataAAAA column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_LegalEntityAxis compact oppenheimer_S000006965Member ~</div> 0.0001 -0.0499 -0.0099 -0.0099 0.0141 0.0091 0.0129 0.0129 0.0151 0.0136 0.0131 0.0134 You may qualify for sales charge discounts if you (or you and your spouse) invest, or agree to invest in the future, at least $25,000 in certain funds in the Oppenheimer family of funds. 25000 An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it is possible to lose money by investing in the Fund. The Fund's past investment performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For the period from January 1, 2012 through September 30, 2012, the cumulative return before taxes was 0.01%. 0.0001 2012-09-30 highest return for a calendar quarter was 1.14% (3rd Qtr 2007) 0.0114 lowest return for a calendar quarter was 0.00% (most recently in 4th Qtr 2011) 0.0000 https://www.oppenheimerfunds.com/fund/investors/overview/CashReserves 1.800.225.5677 1989-01-03 1993-08-17 1993-12-01 2001-03-01 After discussions with the Fund's Board of Trustees, the Manager has voluntarily agreed to limit the Fund's management fee so that the fees do not exceed an annual rate of 0.40% of the daily net assets for each class of shares. The Manager has also voluntarily undertaken to waive fees and/or reimburse expenses to the extent necessary to assist the Fund in attempting to maintain a positive yield. There is no guarantee that the Fund will maintain a positive yield. The Manager is permitted to recapture previously waived and/or reimbursed fees in any given fiscal year if the recapture would not: (1) cause the Fund to generate a negative daily yield, and (2) exceed amounts previously waived and/or reimbursed under this arrangement during the current and prior three fiscal years. The reimbursement to the Manager of such previous waivers and reimbursements would not include any portion of distribution and/or service fees. This recapture could negatively affect each share class's future yield. The Distributor has voluntarily agreed to set the fee rate it is entitled to receive under the Distribution and/or Service Plans for Class A, Class B, Class C, and Class N shares at 0.00%. Each of these undertakings may not be amended or withdrawn until one year from the date of this prospectus.