Shareholder Report, Holdings (Details)	Jun. 30, 2026
C000032051 \| Roku, Inc.
Holdings [Line Items]
Percent of Net Asset Value	16.10%
C000032051 \| Rocket Lab Corp.
Holdings [Line Items]
Percent of Net Asset Value	11.90%
C000032051 \| Bloom Energy Corp.
Holdings [Line Items]
Percent of Net Asset Value	8.80%
C000032051 \| Coherent Corp.
Holdings [Line Items]
Percent of Net Asset Value	7.70%
C000032051 \| Viasat, Inc.
Holdings [Line Items]
Percent of Net Asset Value	5.20%
C000032051 \| ASM International N.V.
Holdings [Line Items]
Percent of Net Asset Value	4.50%
C000032051 \| Oklo, Inc.
Holdings [Line Items]
Percent of Net Asset Value	4.10%
C000032051 \| Broadcom, Inc.
Holdings [Line Items]
Percent of Net Asset Value	3.70%
C000032051 \| Palantir Technologies, Inc.
Holdings [Line Items]
Percent of Net Asset Value	3.00%
C000032051 \| Robinhood Markets, Inc.
Holdings [Line Items]
Percent of Net Asset Value	2.90%
C000032051 \| Other Net Cash
Holdings [Line Items]
Percent of Net Asset Value	6.30%
C000032051 \| Giant Cap (More than $25B)
Holdings [Line Items]
Percent of Net Asset Value	47.90%
C000032051 \| Large Cap ($5-$25B)
Holdings [Line Items]
Percent of Net Asset Value	31.40%
C000032051 \| Mid Cap ($1-$5B)
Holdings [Line Items]
Percent of Net Asset Value	11.30%
C000032051 \| Small Cap ($250M - $1B)
Holdings [Line Items]
Percent of Net Asset Value	1.10%
C000032051 \| Micro Cap (less than $250M)
Holdings [Line Items]
Percent of Net Asset Value	2.00%
C000032051 \| Net Cash
Holdings [Line Items]
Percent of Net Asset Value	6.30%
C000032051 \| United States and Other Assets and Liabilities
Holdings [Line Items]
Percent of Net Asset Value	95.50%
C000032051 \| Other Industries
Holdings [Line Items]
Percent of Net Asset Value	3.30%
C000032051 \| Telecommunications
Holdings [Line Items]
Percent of Net Asset Value	2.70%
C000032051 \| Financial
Holdings [Line Items]
Percent of Net Asset Value	3.10%
C000032051 \| Electric
Holdings [Line Items]
Percent of Net Asset Value	4.10%
C000032051 \| Communications
Holdings [Line Items]
Percent of Net Asset Value	5.20%
C000032051 \| Software
Holdings [Line Items]
Percent of Net Asset Value	6.10%
C000032051 \| Electronics
Holdings [Line Items]
Percent of Net Asset Value	7.70%
C000032051 \| Industrials
Holdings [Line Items]
Percent of Net Asset Value	8.80%
C000032051 \| Semiconductors
Holdings [Line Items]
Percent of Net Asset Value	9.30%
C000032051 \| Defense & Aerospace
Holdings [Line Items]
Percent of Net Asset Value	20.90%
C000032051 \| Internet
Holdings [Line Items]
Percent of Net Asset Value	22.50%
C000032051 \| Netherlands
Holdings [Line Items]
Percent of Net Asset Value	4.50%
C000052080 \| Bloom Energy Corp.
Holdings [Line Items]
Percent of Net Asset Value	20.70%
C000052080 \| Oklo, Inc.
Holdings [Line Items]
Percent of Net Asset Value	7.10%
C000052080 \| Corning, Inc.
Holdings [Line Items]
Percent of Net Asset Value	11.30%
C000052080 \| Quanta Services, Inc.
Holdings [Line Items]
Percent of Net Asset Value	10.30%
C000052080 \| ABB, Ltd. - SP
Holdings [Line Items]
Percent of Net Asset Value	5.20%
C000052080 \| Axcelis Technologies, Inc.
Holdings [Line Items]
Percent of Net Asset Value	5.20%
C000052080 \| Enphase Energy, Inc.
Holdings [Line Items]
Percent of Net Asset Value	4.40%
C000052080 \| The Williams Cos., Inc.
Holdings [Line Items]
Percent of Net Asset Value	4.10%
C000052080 \| ON Semiconductor Corp.
Holdings [Line Items]
Percent of Net Asset Value	3.90%
C000052080 \| GE Vernova, Inc.
Holdings [Line Items]
Percent of Net Asset Value	3.20%
C000052080 \| Other Net Cash
Holdings [Line Items]
Percent of Net Asset Value	(3.80%)
C000052080 \| Giant Cap (More than $25B)
Holdings [Line Items]
Percent of Net Asset Value	74.00%
C000052080 \| Large Cap ($5-$25B)
Holdings [Line Items]
Percent of Net Asset Value	21.20%
C000052080 \| Mid Cap ($1-$5B)
Holdings [Line Items]
Percent of Net Asset Value	6.00%
C000052080 \| Small Cap ($250M - $1B)
Holdings [Line Items]
Percent of Net Asset Value	1.50%
C000052080 \| Micro Cap (less than $250M)
Holdings [Line Items]
Percent of Net Asset Value	1.10%
C000052080 \| Net Cash
Holdings [Line Items]
Percent of Net Asset Value	(3.80%)
C000052080 \| United States and Other Assets and Liabilities
Holdings [Line Items]
Percent of Net Asset Value	82.80%
C000052080 \| Other Industries
Holdings [Line Items]
Percent of Net Asset Value	1.60%
C000052080 \| Telecommunications
Holdings [Line Items]
Percent of Net Asset Value	11.30%
C000052080 \| Electric
Holdings [Line Items]
Percent of Net Asset Value	8.70%
C000052080 \| Electronics
Holdings [Line Items]
Percent of Net Asset Value	7.10%
C000052080 \| Industrials
Holdings [Line Items]
Percent of Net Asset Value	28.60%
C000052080 \| Semiconductors
Holdings [Line Items]
Percent of Net Asset Value	14.70%
C000052080 \| Building Materials
Holdings [Line Items]
Percent of Net Asset Value	2.00%
C000052080 \| Oil&Gas
Holdings [Line Items]
Percent of Net Asset Value	2.70%
C000052080 \| Pipelines
Holdings [Line Items]
Percent of Net Asset Value	4.10%
C000052080 \| Commercial Services
Holdings [Line Items]
Percent of Net Asset Value	10.30%
C000052080 \| Energy
Holdings [Line Items]
Percent of Net Asset Value	12.70%
C000052080 \| Netherlands
Holdings [Line Items]
Percent of Net Asset Value	3.50%
C000052080 \| Spain
Holdings [Line Items]
Percent of Net Asset Value	0.10%
C000052080 \| Japan
Holdings [Line Items]
Percent of Net Asset Value	1.20%
C000052080 \| Ireland
Holdings [Line Items]
Percent of Net Asset Value	1.50%
C000052080 \| France
Holdings [Line Items]
Percent of Net Asset Value	2.70%
C000052080 \| Denmark
Holdings [Line Items]
Percent of Net Asset Value	2.80%
C000052080 \| Switzerland
Holdings [Line Items]
Percent of Net Asset Value	5.40%