Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

T. Rowe Price Institutional International Funds, Inc.

Prospectus Date

rr_ProspectusDate

Mar. 01, 2015

T. Rowe Price Institutional Global Value Equity Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

SUMMARY

T. Rowe Price Institutional Global Value
Equity Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks long-term capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

Fees and Expenses of the Fund

Shareholder fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

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

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

February 29, 2016

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 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 88.l% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

88.10%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This 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 the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year, the fund’s operating expenses remain the same, and the expense limitation currently in place is not renewed. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Investments, Risks, and Performance

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The fund normally invests at least 80% of its net assets (including any borrowings for investment purposes) in equity securities issued by companies throughout the world. The percentage of assets allocated to investments outside the U.S. will vary according to the portfolio manager's outlook. However, under normal conditions, at least 40% of the fund's net assets will be invested in companies outside the U.S. (and at least 30% of its net assets will be invested in companies outside the U.S. if foreign market conditions are not favorable). The fund invests in companies across a broad range of industries in the U.S. and developed markets and, to a lesser extent, emerging markets. Although the fund may invest in companies of any size, investments will generally be made in stocks of large- and mid-cap companies.

While the fund invests with an awareness of the global economic landscape and the outlook for certain industries and countries, stock selection is driven mainly by fundamental research that seeks to identify companies that are undervalued but have the potential for improving earnings over time. The fund's value approach to investing relies on a global research team that searches for companies that appear to be undervalued by various measures and may be temporarily out of favor but have good prospects for capital appreciation or dividend growth.

In selecting investments, the fund generally favors companies with one or more of the following characteristics:

• low valuation on various earnings, book value, sales, and cash flow metrics, in absolute terms and/or relative to the company's peers or its own historical norm;

• low valuation relative to a company's fundamentals;

• companies that may benefit from restructuring activity or other turnaround opportunities;

• a sound balance sheet and other positive financial characteristics; and

• above-average dividend yield and/or the potential to grow dividends.

The fund may sell securities for a variety of reasons, such as to secure gains, limit losses, or redeploy assets into more promising opportunities.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

As with any mutual fund, there is no guarantee that the fund will achieve its objective. The fund's share price fluctuates, which means you could lose money by investing in the fund. The principal risks of investing in this fund are summarized as follows:

Active management risk The fund is subject to the risk that the investment adviser's judgments about the attractiveness, value, or potential appreciation of the fund's investments may prove to be incorrect. If the securities selected and strategies employed by the fund fail to produce the intended results, the fund could underperform other funds with similar objectives and investment strategies.

Risks of stock investing Stocks generally fluctuate in value more than bonds and may decline significantly over short time periods. There is a chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The value of a stock in which the fund invests may decline due to general weakness in the stock market or because of factors that affect a company or a particular industry.

International investing risk Investing in the securities of non-U.S. issuers involves special risks not typically associated with investing in U.S. issuers. International securities tend to be more volatile and less liquid than investments in U.S. securities and may lose value because of adverse political, social, or economic developments overseas, or due to changes in the exchange rates between foreign currencies and the U.S. dollar. In addition, international investments are subject to settlement practices and regulatory and financial reporting standards that differ from those of the U.S. These risks are heightened for the fund's investments in emerging markets.

Investment style risk Different investment styles tend to shift in and out of favor depending on market conditions and investor sentiment. The fund's value approach to investing could cause it to underperform other stock funds that employ a different investment style. The intrinsic value of a stock with value characteristics may not be fully recognized by the market for a long time or a stock judged to be undervalued may actually be appropriately priced at a low level.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, which means you could lose money by investing in the fund.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The bar chart showing calendar year returns and the average annual total returns table indicate risk by illustrating how much returns can differ from one year to the next and how fund performance compares with that of a comparable market index. The fund’s past performance (before and after taxes) is not necessarily an indication of future performance.

The fund can also experience short-term performance swings, as shown by the best and worst calendar quarter returns during the years depicted.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The bar chart showing calendar year returns and the average annual total returns table indicate risk by illustrating how much returns can differ from one year to the next and how fund performance compares with that of a comparable market index.

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

1-800-638-8790

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

troweprice.com

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund’s past performance (before and after taxes) is not necessarily an indication of future performance.

Bar Chart [Heading]

rr_BarChartHeading

Institutional Global Value Equity Fund
Calendar Year Returns

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

	Quarter  Ended	Total Return
Best Quarter	9/30/13	9.48%
Worst Quarter	9/30/14	-2.87%

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns

Periods ended
December 31, 2014

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

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

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as a 401(k) account or individual retirement account.

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

In some cases, the figure shown under “returns after taxes on distributions and sale of fund shares” may be higher than the figure shown under “returns before taxes” because the calculations assume the investor received a tax deduction for any loss incurred on the sale of shares.

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

In addition, the average annual total returns table shows hypothetical after-tax returns to suggest how taxes paid by a shareholder may influence returns. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as a 401(k) account or individual retirement account. In some cases, the figure shown under “returns after taxes on distributions and sale of fund shares” may be higher than the figure shown under “returns before taxes” because the calculations assume the investor received a tax deduction for any loss incurred on the sale of shares.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

Updated performance information is available through troweprice.com or may be obtained by calling 1-800-638-8790.

T. Rowe Price Institutional Global Value Equity Fund | T. Rowe Price Institutional Global Value Equity Fund

Risk/Return:

rr_RiskReturnAbstract

Redemption fee (as a percentage of amount redeemed on shares held for 90 days or less)

rr_RedemptionFeeOverRedemption

2.00%

Management fees

rr_ManagementFeesOverAssets

0.65%

Other expenses

rr_OtherExpensesOverAssets

2.42%

Total annual fund operating expenses

rr_ExpensesOverAssets

3.07%

Fee waiver/expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(2.32%)

^[1]

Total annual fund operating expenses after fee waiver/expense reimbursement

rr_NetExpensesOverAssets

0.75%

^[1]

1 year

rr_ExpenseExampleYear01

77

3 years

rr_ExpenseExampleYear03

729

5 years

rr_ExpenseExampleYear05

1,407

10 years

rr_ExpenseExampleYear10

3,220

2013

rr_AnnualReturn2013

30.92%

2014

rr_AnnualReturn2014

7.70%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2013

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

9.48%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2014

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(2.87%)

1 Year

rr_AverageAnnualReturnYear01

7.70%

Since inception

rr_AverageAnnualReturnSinceInception

20.80%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 26, 2012

T. Rowe Price Institutional Global Value Equity Fund | Returns after taxes on distributions | T. Rowe Price Institutional Global Value Equity Fund

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

3.59%

Since inception

rr_AverageAnnualReturnSinceInception

17.52%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 26, 2012

T. Rowe Price Institutional Global Value Equity Fund | Returns after taxes on distributions and sale of fund shares | T. Rowe Price Institutional Global Value Equity Fund

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

6.97%

Since inception

rr_AverageAnnualReturnSinceInception

15.64%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 26, 2012

T. Rowe Price Institutional Global Value Equity Fund | MSCI World Index (reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

5.50%

Since inception

rr_AverageAnnualReturnSinceInception

17.54%

T. Rowe Price Institutional Global Value Equity Fund | Lipper Global Large-Cap Value Funds Average

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

4.19%

Since inception

rr_AverageAnnualReturnSinceInception

15.43%

^[2]

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 31, 2012

[1] T. Rowe Price Associates, Inc. has agreed (through February 29, 2016) to waive its fees and/or bear any expenses (excluding interest, expenses related to borrowings, taxes and brokerage, extraordinary expenses, and acquired fund fees) that would cause the fund's ratio of expenses to average daily net assets to exceed 0.75%. Termination of the agreement would require approval by the fund's Board of Directors. Fees waived and expenses paid under this agreement are subject to reimbursement to T. Rowe Price Associates, Inc. by the fund whenever the fund's expense ratio is below 0.75%. However, no reimbursement will be made more than three years after the waiver or payment, or if it would result in the expense ratio exceeding 0.75% (excluding interest, expenses related to borrowings, taxes and brokerage, extraordinary expenses, and acquired fund fees).

[2] Returns as of 7/31/12.