v3.26.1
S000009876 [Member] Average Annual Total Returns
 12 Months Ended 60 Months Ended 106 Months Ended 120 Months Ended
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Class Z        
Prospectus [Line Items]        
Average Annual Return, Percent 9.01% 6.41%   12.16%
Class N        
Prospectus [Line Items]        
Average Annual Return, Percent 8.77% 6.19%   11.93%
Class N | After Taxes on Distributions        
Prospectus [Line Items]        
Average Annual Return, Percent 5.98% 3.55%   8.83%
Class N | After Taxes on Distributions and Sales        
Prospectus [Line Items]        
Average Annual Return, Percent 7.21% 4.55%   9.09%
Class I        
Prospectus [Line Items]        
Average Annual Return, Percent 8.96% 6.35% 12.07% [1]
Performance Inception Date     Feb. 24, 2017  
Class I | S&P 500® Index (reflects no deduction for fees, expenses, or taxes)        
Prospectus [Line Items]        
Average Annual Return, Percent 17.88% 14.42% 14.66% [1] 14.82%
Performance Inception Date     Feb. 24, 2017  
Class I | Russell Midcap® Growth Index (reflects no deduction for fees, expenses, or taxes)        
Prospectus [Line Items]        
Average Annual Return, Percent 8.66% 6.65% 12.49% [1] 12.49%
Performance Inception Date     Feb. 24, 2017  
[1] Class I and Index performance shown reflects performance since the inception date of the Fund's Class I shares on February 24, 2017.