Shareholder Report, Average Annual Return (Details)	12 Months Ended	60 Months Ended	104 Months Ended	120 Months Ended	152 Months Ended	183 Months Ended	206 Months Ended		245 Months Ended
	Dec. 31, 2025	Dec. 31, 2025	Dec. 31, 2025	Dec. 31, 2025	Dec. 31, 2025	Dec. 31, 2025	Dec. 31, 2025	Dec. 31, 2025	Dec. 31, 2025
C000094853
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class A with load
Average Annual Return, Percent	3.73%	2.28%		3.47%		2.94%
C000094854
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class C
Average Annual Return, Percent	6.48%	2.39%		3.29%		2.81%
C000190722
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class N
C000094855
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class Y
C000021802
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class A with load
Average Annual Return, Percent	8.26%	13.78%		13.01%					11.56%
C000021804
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class C
Average Annual Return, Percent	13.03%	14.28%		13.00%					9.07%
C000190720
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class N
C000021805
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class Y
C000069913
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class A with load
Average Annual Return, Percent	5.67%	9.49%		8.55%				10.81%
C000069914
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class C
Average Annual Return, Percent	10.59%	9.98%		8.53%			10.81%
C000128764
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class N
C000069915
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class Y
Without Sales Load [Member] | C000094853
Average Annual Return [Line Items]
Average Annual Return, Percent	8.29%	3.16%		3.92%		3.23%
Without Sales Load [Member] | C000094854
Average Annual Return [Line Items]
Average Annual Return, Percent	7.48%	2.39%		3.29%		2.81%
Without Sales Load [Member] | C000190722
Average Annual Return [Line Items]
Average Annual Return, Percent	8.62%	3.47%	3.93%
Without Sales Load [Member] | C000094855
Average Annual Return [Line Items]
Average Annual Return, Percent	8.58%	3.42%		4.17%		3.48%
Without Sales Load [Member] | C000021802
Average Annual Return [Line Items]
Average Annual Return, Percent	14.86%	15.14%		13.68%					11.64%
Without Sales Load [Member] | C000021804
Average Annual Return [Line Items]
Average Annual Return, Percent	14.03%	14.28%		13.00%					9.07%
Without Sales Load [Member] | C000190720
Average Annual Return [Line Items]
Average Annual Return, Percent	15.20%	15.51%	13.48%
Without Sales Load [Member] | C000021805
Average Annual Return [Line Items]
Average Annual Return, Percent	15.15%	15.43%		13.97%					7.79%
Without Sales Load [Member] | C000069913
Average Annual Return [Line Items]
Average Annual Return, Percent	12.14%	10.80%		9.19%				11.20%
Without Sales Load [Member] | C000069914
Average Annual Return [Line Items]
Average Annual Return, Percent	11.30%	9.98%		8.53%			10.81%
Without Sales Load [Member] | C000128764
Average Annual Return [Line Items]
Average Annual Return, Percent	12.44%	11.13%		9.54%	9.97%
Without Sales Load [Member] | C000069915
Average Annual Return [Line Items]
Average Annual Return, Percent	12.39%	11.08%		9.47%			11.48%
Natixis Index: Bloomberg U.S. Aggregate Bond Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Bloomberg U.S. Aggregate Bond Index
Average Annual Return, Percent	7.30%	(0.36%)		2.01%		0.00%
Natixis Index: Bloomberg U.S. Aggregate Bond Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Bloomberg U.S. Aggregate Bond Index
Average Annual Return, Percent	7.30%	(0.36%)		2.01%		0.00%
Natixis Index: Bloomberg U.S. Aggregate Bond Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Bloomberg U.S. Aggregate Bond Index
Average Annual Return, Percent	7.30%	(0.36%)	1.84%
Natixis Index: Bloomberg U.S. Aggregate Bond Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Bloomberg U.S. Aggregate Bond Index
Average Annual Return, Percent	7.30%	(0.36%)		2.01%		0.00%
NATIXIS INDEX: Russell 3000® Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Russell 3000<sup style="inset: 1.5px 0px 4px; box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 700; grid-area: auto; line-height: 0px; margin: 0px; overflow: visible; position: relative; text-align: center; text-align-last: auto; white-space-collapse: preserve-breaks;">®</sup> Index
Average Annual Return, Percent	17.15%	13.15%		14.29%				0.00%
NATIXIS INDEX: Russell 3000® Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Russell 3000<sup style="inset: 1.5px 0px 4px; box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 700; grid-area: auto; line-height: 0px; margin: 0px; overflow: visible; position: relative; text-align: center; text-align-last: auto; white-space-collapse: preserve-breaks;">®</sup> Index
Average Annual Return, Percent	17.15%	13.15%		14.29%			0.00%
NATIXIS INDEX: Russell 3000® Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Russell 3000<sup style="inset: 1.5px 0px 4px; box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 700; grid-area: auto; line-height: 0px; margin: 0px; overflow: visible; position: relative; text-align: center; text-align-last: auto; white-space-collapse: preserve-breaks;">®</sup> Index
Average Annual Return, Percent	17.15%	13.15%		14.29%	0.00%
NATIXIS INDEX: Russell 3000® Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Russell 3000<sup style="inset: 1.5px 0px 4px; box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 700; grid-area: auto; line-height: 0px; margin: 0px; overflow: visible; position: relative; text-align: center; text-align-last: auto; white-space-collapse: preserve-breaks;">®</sup> Index
Average Annual Return, Percent	17.15%	13.15%		14.29%			0.00%
NATIXIS INDEX: ICE BofA U.S. 3-Month Treasury Bill Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	ICE BofA U.S. 3-Month Treasury Bill Index
Average Annual Return, Percent	4.18%	3.17%		2.18%		0.00%
NATIXIS INDEX: ICE BofA U.S. 3-Month Treasury Bill Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	ICE BofA U.S. 3-Month Treasury Bill Index
Average Annual Return, Percent	4.18%	3.17%		2.18%		0.00%
NATIXIS INDEX: ICE BofA U.S. 3-Month Treasury Bill Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	ICE BofA U.S. 3-Month Treasury Bill Index
Average Annual Return, Percent	4.18%	3.17%	2.45%
NATIXIS INDEX: ICE BofA U.S. 3-Month Treasury Bill Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	ICE BofA U.S. 3-Month Treasury Bill Index
Average Annual Return, Percent	4.18%	3.17%		2.18%		0.00%
NATIXIS INDEX: S&P 500® Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	S&P 500<sup style="inset: 1.5px 0px 4px; box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 700; grid-area: auto; line-height: 0px; margin: 0px; overflow: visible; position: relative; text-align: center; text-align-last: auto; white-space-collapse: preserve-breaks;">®</sup> Index
Average Annual Return, Percent	17.88%	14.42%		14.82%					0.00%
NATIXIS INDEX: S&P 500® Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	S&P 500<sup style="inset: 1.5px 0px 4px; box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 700; grid-area: auto; line-height: 0px; margin: 0px; overflow: visible; position: relative; text-align: center; text-align-last: auto; white-space-collapse: preserve-breaks;">®</sup> Index
Average Annual Return, Percent	17.88%	14.42%		14.82%					0.00%
NATIXIS INDEX: S&P 500® Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	S&P 500<sup style="inset: 1.5px 0px 4px; box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 700; grid-area: auto; line-height: 0px; margin: 0px; overflow: visible; position: relative; text-align: center; text-align-last: auto; white-space-collapse: preserve-breaks;">®</sup> Index
Average Annual Return, Percent	17.88%	14.42%	14.77%
NATIXIS INDEX: S&P 500® Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	S&P 500<sup style="inset: 1.5px 0px 4px; box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 700; grid-area: auto; line-height: 0px; margin: 0px; overflow: visible; position: relative; text-align: center; text-align-last: auto; white-space-collapse: preserve-breaks;">®</sup> Index
Average Annual Return, Percent	17.88%	14.42%		14.82%					0.00%
NATIXIS INDEX: Russell Midcap® Value Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Russell Midcap<sup style="inset: 1.5px 0px 4px; box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 700; grid-area: auto; line-height: 0px; margin: 0px; overflow: visible; position: relative; text-align: center; text-align-last: auto; white-space-collapse: preserve-breaks;">®</sup> Value Index
Average Annual Return, Percent	11.05%	9.83%		9.78%				0.00%
NATIXIS INDEX: Russell Midcap® Value Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Russell Midcap<sup style="inset: 1.5px 0px 4px; box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 700; grid-area: auto; line-height: 0px; margin: 0px; overflow: visible; position: relative; text-align: center; text-align-last: auto; white-space-collapse: preserve-breaks;">®</sup> Value Index
Average Annual Return, Percent	11.05%	9.83%		9.78%			0.00%
NATIXIS INDEX: Russell Midcap® Value Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Russell Midcap<sup style="inset: 1.5px 0px 4px; box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 700; grid-area: auto; line-height: 0px; margin: 0px; overflow: visible; position: relative; text-align: center; text-align-last: auto; white-space-collapse: preserve-breaks;">®</sup> Value Index
Average Annual Return, Percent	11.05%	9.83%		9.78%	0.00%
NATIXIS INDEX: Russell Midcap® Value Index
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Russell Midcap<sup style="inset: 1.5px 0px 4px; box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 700; grid-area: auto; line-height: 0px; margin: 0px; overflow: visible; position: relative; text-align: center; text-align-last: auto; white-space-collapse: preserve-breaks;">®</sup> Value Index
Average Annual Return, Percent	11.05%	9.83%		9.78%			0.00%