Should Match : 1. 123-456-789 2. 123.789.456 3. 963 456 741
Should Not Match : 1. 123-456.789 2. 123 789-456 3. 963.456 741
Regex: (?<!\d)\d{3}[\d$diff]{3,10}\d{3}(?!\d))
$diff contains :  -.