S000050481 [Member] Average Annual Total Returns	12 Months Ended	60 Months Ended	120 Months Ended	124 Months Ended
S000050481 [Member] Average Annual Total Returns	Dec. 31, 2025	Dec. 31, 2025	Dec. 31, 2025	Dec. 31, 2025
Beta Thematic Emerging Markets ex-China Index (reflects no deductions for fees, expenses or taxes)
Prospectus [Line Items]
Average Annual Return, Percent	34.53%	7.93%	10.22%
MSCI Emerging Markets Index (Net) (reflects reinvested dividends net of withholding taxes but reflects no deductions for fees, expenses or other taxes)
Prospectus [Line Items]
Average Annual Return, Percent	33.57%	4.20%	8.42%
C000159357 [Member]
Prospectus [Line Items]
Average Annual Return, Percent	32.98%	7.45%	10.32%
Performance Inception Date				Sep. 02, 2015
C000159357 [Member] \| After Taxes on Distributions
Prospectus [Line Items]
Average Annual Return, Percent	31.77%	6.91%	9.60%
Performance Inception Date				Sep. 02, 2015
C000159357 [Member] \| After Taxes on Distributions and Sales
Prospectus [Line Items]
Average Annual Return, Percent	20.04%	5.80%	8.35%
Performance Inception Date				Sep. 02, 2015