Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2022	Feb. 20, 2023	Jun. 30, 2022
Document and Entity Information
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2022
Document Transition Report	false
Entity File Number	001-38727
Entity Registrant Name	PennyMac Financial Services, Inc.
Entity Central Index Key	0001745916
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	83-1098934
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
Title of 12(b) Security	Common Stock, $0.0001 par value
Trading Symbol	PFSI
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
ICFR Auditor Attestation Flag	true
Entity Public Float			$ 1,244,422,870
Entity Common Stock, Shares Outstanding		50,033,203
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Auditor Name	Deloitte & Touche LLP
Auditor Firm ID	34
Auditor Location	Los Angeles, California