Shareholder Report, Average Annual Return (Details) |
6 Months Ended | 12 Months Ended | 60 Months Ended | 120 Months Ended |
|---|---|---|---|---|
Aug. 31, 2026 |
Aug. 31, 2026 |
Aug. 31, 2026 |
Aug. 31, 2026 |
|
| C000029067 | ||||
| Average Annual Return [Line Items] | ||||
| Line Graph and Table Measure Name | CM Advisors Fixed Income Fund | |||
| Without Sales Load [Member] | C000029067 | ||||
| Average Annual Return [Line Items] | ||||
| Average Annual Return, Percent | 3.12% | 4.57% | 3.07% | |
| 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 | 1.89% | (0.29%) | 1.40% |