v3.26.1
Shareholder Report
 6 Months Ended
Jun. 30, 2026
USD ($)
Holding
Shareholder Report [Line Items]  
Document Type N-CSRS
Amendment Flag false
Registrant Name T. ROWE PRICE SPECTRUM FUND, INC.
Entity Central Index Key 0000808303
Entity Investment Company Type N-1A
Document Period End Date Jun. 30, 2026
Shareholder Report Annual or Semi-Annual Semi-Annual Shareholder Report
C000005513  
Shareholder Report [Line Items]  
Fund Name Spectrum Diversified Equity Fund
Class Name Investor Class
Trading Symbol PRSGX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Spectrum Diversified Equity Fund (the "fund") for the period of January 1, 2026 to June 30, 2026.
Additional Information [Text Block] You can find the fund’s prospectus, financial information on Form N‑CSR (which includes required tax information for dividends), holdings, proxy voting information, and other information atwww.troweprice.com/prospectus. You can also request this information without charge by contacting T. Rowe Price at 1‑800‑638‑5660 or info@troweprice.com or contacting your intermediary.
Material Fund Change Notice [Text Block]  
Additional Information Phone Number 1‑800‑638‑5660
Additional Information Email <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 13.3333px; font-weight: 400; grid-area: auto; line-height: 17.3333px; margin: 0px; overflow: visible; text-align: justify; text-align-last: left; white-space-collapse: preserve-breaks;">info@troweprice.com</span>
Additional Information Website www.troweprice.com/prospectus
Expenses [Text Block]

What were the fund costs for the last six months? (based on a hypothetical $10,000 investment)

Table Summary
 
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Spectrum Diversified Equity Fund - Investor Class
$35
0.67%
Expenses Paid, Amount $ 35
Expense Ratio, Percent 0.67%
Updated Performance Information Location [Text Block]

If you invest directly with T. Rowe Price, you can elect to receive future shareholder reports or other important documents through electronic delivery by enrolling at www.troweprice.com/paperless. If you invest through a financial intermediary such as an investment advisor, a bank, retirement plan sponsor or a brokerage firm, please contact that organization and ask if it can provide electronic delivery.

Visit www.troweprice.com/en/us/market-data-disclosures for additional legal notices & disclaimers.
AssetsNet $ 4,483,400,000
Holdings Count | Holding 16
InvestmentCompanyPortfolioTurnover 7.40%
Additional Fund Statistics [Text Block]

What are some fund statistics?

Fund Statistics

Table Summary
Total Net Assets (000s)
$4,483,400
Number of Portfolio Holdings
16
Additional Fund Statistics Significance or Limits [Text Block]
Table Summary
Portfolio Turnover Rate
7.4%
Holdings [Text Block]

Asset Allocation (as a % of Net Assets)

Table Summary
Domestic Equity Funds
99.9%
Short-Term and Other
0.1
Largest Holdings [Text Block]

Top Ten Holdings (as a % of Net Assets)

Table Summary
T. Rowe Price Value Fund
14.0%
T. Rowe Price All-Cap Opportunities Fund
11.1
T. Rowe Price U.S. Large-Cap Core Fund
11.1
T. Rowe Price Blue Chip Growth Fund
10.8
T. Rowe Price Growth Stock Fund
10.6
T. Rowe Price Equity Income Fund
10.5
T. Rowe Price New Horizons Fund
4.9
T. Rowe Price Small-Cap Value Fund
4.9
T. Rowe Price Growth Stock ETF
3.8
T. Rowe Price Mid-Cap Value Fund
3.7
Material Fund Change [Text Block]
Updated Prospectus Web Address www.troweprice.com/paperless
C000227148  
Shareholder Report [Line Items]  
Fund Name Spectrum Diversified Equity Fund
Class Name I Class
Trading Symbol TSVPX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Spectrum Diversified Equity Fund (the "fund") for the period of January 1, 2026 to June 30, 2026.
Additional Information [Text Block] You can find the fund’s prospectus, financial information on Form N‑CSR (which includes required tax information for dividends), holdings, proxy voting information, and other information atwww.troweprice.com/prospectus. You can also request this information without charge by contacting T. Rowe Price at 1‑800‑638‑5660 or info@troweprice.com or contacting your intermediary.
Material Fund Change Notice [Text Block]  
Additional Information Phone Number 1‑800‑638‑5660
Additional Information Email <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 13.3333px; font-weight: 400; grid-area: auto; line-height: 17.3333px; margin: 0px; overflow: visible; text-align: justify; text-align-last: left; white-space-collapse: preserve-breaks;">info@troweprice.com</span>
Additional Information Website www.troweprice.com/prospectus
Expenses [Text Block]

What were the fund costs for the last six months? (based on a hypothetical $10,000 investment)

Table Summary
 
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Spectrum Diversified Equity Fund - I Class
$27
0.52%
Expenses Paid, Amount $ 27
Expense Ratio, Percent 0.52%
Updated Performance Information Location [Text Block]

If you invest directly with T. Rowe Price, you can elect to receive future shareholder reports or other important documents through electronic delivery by enrolling at www.troweprice.com/paperless. If you invest through a financial intermediary such as an investment advisor, a bank, retirement plan sponsor or a brokerage firm, please contact that organization and ask if it can provide electronic delivery.

Visit www.troweprice.com/en/us/market-data-disclosures for additional legal notices & disclaimers.
AssetsNet $ 4,483,400,000
Holdings Count | Holding 16
InvestmentCompanyPortfolioTurnover 7.40%
Additional Fund Statistics [Text Block]

What are some fund statistics?

Fund Statistics

Table Summary
Total Net Assets (000s)
$4,483,400
Number of Portfolio Holdings
16
Additional Fund Statistics Significance or Limits [Text Block]
Table Summary
Portfolio Turnover Rate
7.4%
Holdings [Text Block]

Asset Allocation (as a % of Net Assets)

Table Summary
Domestic Equity Funds
99.9%
Short-Term and Other
0.1
Largest Holdings [Text Block]

Top Ten Holdings (as a % of Net Assets)

Table Summary
T. Rowe Price Value Fund
14.0%
T. Rowe Price All-Cap Opportunities Fund
11.1
T. Rowe Price U.S. Large-Cap Core Fund
11.1
T. Rowe Price Blue Chip Growth Fund
10.8
T. Rowe Price Growth Stock Fund
10.6
T. Rowe Price Equity Income Fund
10.5
T. Rowe Price New Horizons Fund
4.9
T. Rowe Price Small-Cap Value Fund
4.9
T. Rowe Price Growth Stock ETF
3.8
T. Rowe Price Mid-Cap Value Fund
3.7
Material Fund Change [Text Block]
Updated Prospectus Web Address www.troweprice.com/paperless