| Cover | Mar. 03, 2023 |
| Cover [Abstract] | |
| Document Type | 8-K/A |
| Amendment Flag | true |
| Amendment Description | This Amendment No. 1 amends the Current Report on Form 8-K of PennyMac Financial Services, Inc. (the “Company”) filed on March 9, 2023, which reported that Vandad Fartaj ceased serving as the Company’s Senior Managing Director and Chief Investment Officer on March 3, 2023. The information set forth in the initial 8-K is incorporated herein by reference. |
| Document Period End Date | Mar. 03, 2023 |
| Entity File Number | 001-38727 |
| Entity Registrant Name | PennyMac Financial Services, Inc. |
| Entity Central Index Key | 0001745916 |
| Entity Tax Identification Number | 83-1098934 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | 3043 Townsgate Road |
| Entity Address, City or Town | Westlake Village |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 91361 |
| City Area Code | 818 |
| Local Phone Number | 224-7442 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $0.0001 par value |
| Trading Symbol | PFSI |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
