| Document and Entity Information | Dec. 05, 2024 |
| Cover [Abstract] | |
| Amendment Flag | true |
| Entity Central Index Key | 0001397911 |
| Document Type | 8-K/A |
| Document Period End Date | Dec. 05, 2024 |
| Entity Registrant Name | LPL Financial Holdings Inc. |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-34963 |
| Entity Tax Identification Number | 20-3717839 |
| Entity Address, Address Line One | 4707 Executive Drive |
| Entity Address, City or Town | San Diego |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 92121 |
| City Area Code | (800) |
| Local Phone Number | 877-7210 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock - par value $0.001 per share |
| Trading Symbol | LPLA |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Amendment Description | This Amendment No. 1 on Form 8-K/A is being filed solely to ensure two additional item number tags (Item 2.03 and Item 9.01) are reflected in the EDGAR system for the submission of the Current Report on Form 8-K filed with the Securities and Exchange Commission on December 5, 2024. No substantive changes have been made to the disclosures previously provided. |
