const regex = /(^[^-]+)-([^-]+)-/gm;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('(^[^-]+)-([^-]+)-', 'gm')
const str = `12055371-1-Florence - BW Letter of Intent HB Comments 9-4-14-2.DOCX
12057668-2-EB-DUE-M- SBuxbaum FHA Benefit Plans-2.DOCX
12058210-1-Redline Letter of Intent-2.PDF
12058029-3-Florence Hospital--Order Establishing Bid Procedures-HB 9-23-14-2.DOCX
12058020-10-Florence - BW Letter of Intent 10,10,14 Revisions-2.DOCX `;
const subst = `\1|\2|`;
// The substituted value will be contained in the result variable
const result = str.replace(regex, subst);
console.log('Substitution result: ', result);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions