Shareholder Report, Average Annual Return (Details)	12 Months Ended	60 Months Ended	120 Months Ended
Shareholder Report, Average Annual Return (Details)	May 31, 2026	May 31, 2026	May 31, 2026
C000101856 [Member]
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class R Shares
Average Annual Return, Percent	19.83%	1.65%	7.38%
C000198221 [Member]
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class K Shares
Average Annual Return, Percent	20.51%	2.21%	8.00%
C000005983 [Member]
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Investor C Shares (with sales charge)
Average Annual Return, Percent	18.24%	1.13%	6.97%
C000005981 [Member]
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Investor A Shares (with sales charge)
Average Annual Return, Percent	13.85%	0.81%	7.08%
C000005984 [Member]
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Institutional Shares
Average Annual Return, Percent	20.40%	2.15%	7.94%
Without Sales Load [Member] \| C000005983 [Member]
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Investor C Shares
Average Annual Return, Percent	19.24%	1.13%	6.97%
Without Sales Load [Member] \| C000005981 [Member]
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Investor A Shares
Average Annual Return, Percent	20.16%	1.91%	7.65%
MSCI ACWI ex USA Index Net [Member]
Average Annual Return [Line Items]
Line Graph and Table Measure Name	MSCI ACWI ex USA Index (Net)
Average Annual Return, Percent	32.77%	8.77%	9.82%