v3.26.3
Fair Value - Summary of Financial Statement Items Measured at Fair Value on Recurring Basis (Detail) - USD ($)
$ in Thousands
Sep. 30, 2032
Sep. 30, 2031
Sep. 30, 2030
Sep. 30, 2029
Sep. 30, 2028
Sep. 30, 2027
Sep. 30, 2026
Jun. 30, 2026
Dec. 31, 2025
Sep. 30, 2025
 [1]
Jun. 30, 2025
Dec. 31, 2024
Assets:                        
Short-term investments             $ 148,630   $ 190,518      
Mortgage-backed securities             4,305,991   4,452,859      
Loans held for sale             2,870,751   2,699,398      
Mortgage servicing rights             3,513,760 [1] $ 3,575,603 3,644,702 $ 3,668,755 $ 3,739,106 $ 3,867,394
Liabilities:                        
Interest-only security payable $ 34,608 $ 0 $ 0 $ 0 $ 0 $ 0 34,608   37,650      
Derivative and credit risk transfer strip liabilities:                        
Total derivative and credit risk transfer strip liabilities             11,333   6,932      
PennyMac Financial Services, Inc. [Member]                        
Assets:                        
Derivative assets             5,832   6,389      
Derivative assets, Netting             (164)   (142)      
Total derivative assets after netting             5,668   6,247      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             16,620   2,399      
Derivative liabilities, Netting             (164)   (142)      
Total derivative liabilities after netting             16,456   2,257      
PennyMac Financial Services, Inc. [Member] | Interest Rate Lock Commitments with PFSI [Member]                        
Assets:                        
Derivative assets             370   4,605      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             16,456   2,257      
PennyMac Financial Services, Inc. [Member] | Forward Purchase Contracts [Member]                        
Assets:                        
Derivative assets             5,462   1,784      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             164   142      
Nonaffiliates [Member]                        
Assets:                        
Derivative assets             180,190   44,551      
Derivative assets, Netting             (127,189)   5,145      
Total derivative assets after netting             53,001   49,696      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             16,157   17,498      
Derivative liabilities, Netting             (10,055)   (16,565)      
Total derivative liabilities after netting             6,102   933      
Total derivative and credit risk transfer strip liabilities             11,333   6,932      
Nonaffiliates [Member] | Credit Risk Transfer / CRT Derivatives [Member]                        
Assets:                        
Derivative assets [2]             30,695   32,659      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities [2]             0   0      
Nonaffiliates [Member] | Forward Purchase Contracts [Member]                        
Assets:                        
Derivative assets [2]             0   4,113      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities [2]             13,166   158      
Nonaffiliates [Member] | Forward Sale Contracts [Member]                        
Assets:                        
Derivative assets [2]             89,048   2,381      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities [2]             2,959   17,340      
Call Options on Interest Rate Futures Purchase Contracts [Member] | Nonaffiliates [Member]                        
Assets:                        
Derivative assets [2]             88   1,289      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities [2]             0   0      
Put Options On Interest Rate Futures Purchase Contracts | Nonaffiliates [Member]                        
Assets:                        
Derivative assets [2]             5,566   4,109      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities [2]             0   0      
Recurring [Member]                        
Assets:                        
Short-term investments             148,630   190,518      
Mortgage-backed securities             4,305,991   4,452,859      
Loans held for sale             2,870,751   2,699,398      
Loans held for investment             14,401,385   8,532,644      
Total Assets             25,299,186   19,576,064      
Mortgage servicing rights             3,513,760   3,644,702      
Liabilities:                        
Asset-backed financings of the variable interest entities             13,146,200   7,789,303      
Interest-only security payable             34,608   37,650      
Derivative and credit risk transfer strip liabilities:                        
Total liabilities             13,208,597   7,836,142      
Recurring [Member] | Level 1 [Member]                        
Assets:                        
Short-term investments             148,630   190,518      
Mortgage-backed securities             0   0      
Loans held for sale             0   0      
Loans held for investment             0   0      
Total Assets             154,284   195,916      
Mortgage servicing rights             0   0      
Liabilities:                        
Asset-backed financings of the variable interest entities             0   0      
Interest-only security payable             0   0      
Derivative and credit risk transfer strip liabilities:                        
Total liabilities             0   0      
Recurring [Member] | Level 2 [Member]                        
Assets:                        
Short-term investments             0   0      
Mortgage-backed securities             4,230,727   4,380,357      
Loans held for sale             2,868,343   2,695,817      
Loans held for investment             14,400,024   8,530,939      
Total Assets             21,648,397   15,615,391      
Mortgage servicing rights             0   0      
Liabilities:                        
Asset-backed financings of the variable interest entities             13,146,200   7,789,303      
Interest-only security payable             0   0      
Derivative and credit risk transfer strip liabilities:                        
Total liabilities             13,162,521   7,806,943      
Recurring [Member] | Level 3 [Member]                        
Assets:                        
Short-term investments             0   0      
Mortgage-backed securities             75,264   72,502      
Loans held for sale             2,408   3,581      
Loans held for investment             1,361   1,705      
Total Assets             3,623,858   3,759,754      
Mortgage servicing rights             3,513,760   3,644,702      
Liabilities:                        
Asset-backed financings of the variable interest entities             0   0      
Interest-only security payable             34,608   37,650      
Derivative and credit risk transfer strip liabilities:                        
Total liabilities             56,295   45,906      
Recurring [Member] | PennyMac Financial Services, Inc. [Member]                        
Assets:                        
Derivative assets             5,832   6,389      
Derivative assets, Netting             (127,189)   (142)      
Total derivative assets after netting             5,668   6,247      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             16,456   2,399      
Derivative liabilities, Netting             (164)   (142)      
Total derivative liabilities after netting             (16,620)   2,257      
Recurring [Member] | PennyMac Financial Services, Inc. [Member] | Level 1 [Member]                        
Assets:                        
Derivative assets             0   0      
Derivative assets, Netting             0   0      
Total derivative assets after netting             0   0      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             0   0      
Derivative liabilities, Netting             0   0      
Total derivative liabilities after netting             0   0      
Recurring [Member] | PennyMac Financial Services, Inc. [Member] | Level 2 [Member]                        
Assets:                        
Derivative assets             5,462   1,784      
Derivative assets, Netting             0   0      
Total derivative assets after netting             5,462   1,784      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             164   142      
Derivative liabilities, Netting             0   0      
Total derivative liabilities after netting             164   142      
Recurring [Member] | PennyMac Financial Services, Inc. [Member] | Level 3 [Member]                        
Assets:                        
Derivative assets             370   4,605      
Derivative assets, Netting             0   0      
Total derivative assets after netting             370   4,605      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             16,456   2,257      
Derivative liabilities, Netting             0   0      
Total derivative liabilities after netting             16,456   2,257      
Recurring [Member] | PennyMac Financial Services, Inc. [Member] | Interest Rate Lock Commitments with PFSI [Member]                        
Assets:                        
Derivative assets             370   4,605      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             16,456   2,257      
Recurring [Member] | PennyMac Financial Services, Inc. [Member] | Interest Rate Lock Commitments with PFSI [Member] | Level 1 [Member]                        
Assets:                        
Derivative assets             0   0      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             0   0      
Recurring [Member] | PennyMac Financial Services, Inc. [Member] | Interest Rate Lock Commitments with PFSI [Member] | Level 2 [Member]                        
Assets:                        
Derivative assets             0   0      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             0   0      
Recurring [Member] | PennyMac Financial Services, Inc. [Member] | Interest Rate Lock Commitments with PFSI [Member] | Level 3 [Member]                        
Assets:                        
Derivative assets             370   4,605      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             16,456   2,257      
Recurring [Member] | PennyMac Financial Services, Inc. [Member] | Forward Purchase Contracts [Member]                        
Assets:                        
Derivative assets             5,462   1,784      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             164   142      
Recurring [Member] | PennyMac Financial Services, Inc. [Member] | Forward Purchase Contracts [Member] | Level 1 [Member]                        
Assets:                        
Derivative assets             0   0      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             0   0      
Recurring [Member] | PennyMac Financial Services, Inc. [Member] | Forward Purchase Contracts [Member] | Level 2 [Member]                        
Assets:                        
Derivative assets             5,462   1,784      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             164   142      
Recurring [Member] | PennyMac Financial Services, Inc. [Member] | Forward Purchase Contracts [Member] | Level 3 [Member]                        
Assets:                        
Derivative assets             0   0      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             0   0      
Recurring [Member] | Nonaffiliates [Member]                        
Assets:                        
Derivative assets             180,190   44,551      
Derivative assets, Netting             (164)   5,145      
Total derivative assets after netting             53,001   49,696      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             16,157   17,498      
Derivative liabilities, Netting             (10,055)   (16,565)      
Total derivative liabilities after netting             6,102   933      
Total derivative and credit risk transfer strip liabilities             11,333   6,932      
Recurring [Member] | Nonaffiliates [Member] | Credit Risk Transfer Strips [Member]                        
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             5,231   5,999      
Recurring [Member] | Nonaffiliates [Member] | Credit Risk Transfer / CRT Derivatives [Member]                        
Assets:                        
Derivative assets             30,695   32,659      
Recurring [Member] | Nonaffiliates [Member] | Level 1 [Member]                        
Assets:                        
Derivative assets             5,654   5,398      
Derivative assets, Netting             0          
Total derivative assets after netting             5,654   5,398      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             0   0      
Derivative liabilities, Netting             0   0      
Total derivative liabilities after netting             0   0      
Total derivative and credit risk transfer strip liabilities             0   0      
Recurring [Member] | Nonaffiliates [Member] | Level 1 [Member] | Credit Risk Transfer Strips [Member]                        
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             0   0      
Recurring [Member] | Nonaffiliates [Member] | Level 1 [Member] | Credit Risk Transfer / CRT Derivatives [Member]                        
Assets:                        
Derivative assets             0   0      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities, Netting                 0      
Recurring [Member] | Nonaffiliates [Member] | Level 2 [Member]                        
Assets:                        
Derivative assets             143,841   6,494      
Derivative assets, Netting             0          
Total derivative assets after netting             143,841   6,494      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             16,157   17,498      
Derivative liabilities, Netting             0   0      
Total derivative liabilities after netting             16,157   17,498      
Total derivative and credit risk transfer strip liabilities             16,157   17,498      
Recurring [Member] | Nonaffiliates [Member] | Level 2 [Member] | Credit Risk Transfer Strips [Member]                        
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             0   0      
Recurring [Member] | Nonaffiliates [Member] | Level 2 [Member] | Credit Risk Transfer / CRT Derivatives [Member]                        
Assets:                        
Derivative assets             0   0      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities, Netting                 0      
Recurring [Member] | Nonaffiliates [Member] | Level 3 [Member]                        
Assets:                        
Derivative assets             30,695   32,659      
Derivative assets, Netting             0          
Total derivative assets after netting             30,695   32,659      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             0   0      
Derivative liabilities, Netting             0   0      
Total derivative liabilities after netting             0   0      
Total derivative and credit risk transfer strip liabilities             5,231   5,999      
Recurring [Member] | Nonaffiliates [Member] | Level 3 [Member] | Credit Risk Transfer Strips [Member]                        
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             5,231   5,999      
Recurring [Member] | Nonaffiliates [Member] | Level 3 [Member] | Credit Risk Transfer / CRT Derivatives [Member]                        
Assets:                        
Derivative assets             30,695   32,659      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities, Netting                 0      
Recurring [Member] | Nonaffiliates [Member] | Forward Purchase Contracts [Member]                        
Assets:                        
Derivative assets                 4,113      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             13,166   158      
Recurring [Member] | Nonaffiliates [Member] | Forward Purchase Contracts [Member] | Level 1 [Member]                        
Assets:                        
Derivative assets                 0      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             0   0      
Recurring [Member] | Nonaffiliates [Member] | Forward Purchase Contracts [Member] | Level 2 [Member]                        
Assets:                        
Derivative assets                 4,113      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             13,166   158      
Recurring [Member] | Nonaffiliates [Member] | Forward Purchase Contracts [Member] | Level 3 [Member]                        
Assets:                        
Derivative assets                 0      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             0   0      
Recurring [Member] | Nonaffiliates [Member] | Forward Sale Contracts [Member]                        
Assets:                        
Derivative assets             89,048   2,381      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             2,959   17,340      
Recurring [Member] | Nonaffiliates [Member] | Forward Sale Contracts [Member] | Level 1 [Member]                        
Assets:                        
Derivative assets             0   0      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             0   0      
Recurring [Member] | Nonaffiliates [Member] | Forward Sale Contracts [Member] | Level 2 [Member]                        
Assets:                        
Derivative assets             89,048   2,381      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             2,959   17,340      
Recurring [Member] | Nonaffiliates [Member] | Forward Sale Contracts [Member] | Level 3 [Member]                        
Assets:                        
Derivative assets             0   0      
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             0   0      
Recurring [Member] | Nonaffiliates [Member] | Swaptions                        
Assets:                        
Derivative assets             54,793          
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             32          
Recurring [Member] | Nonaffiliates [Member] | Swaptions | Level 1 [Member]                        
Assets:                        
Derivative assets             0          
Recurring [Member] | Nonaffiliates [Member] | Swaptions | Level 2 [Member]                        
Assets:                        
Derivative assets             54,793          
Derivative and credit risk transfer strip liabilities:                        
Derivative liabilities             32          
Recurring [Member] | Nonaffiliates [Member] | Swaptions | Level 3 [Member]                        
Assets:                        
Derivative assets             0          
Recurring [Member] | Call Options on Interest Rate Futures Purchase Contracts [Member] | Nonaffiliates [Member]                        
Assets:                        
Derivative assets             88   1,289      
Recurring [Member] | Call Options on Interest Rate Futures Purchase Contracts [Member] | Nonaffiliates [Member] | Level 1 [Member]                        
Assets:                        
Derivative assets             88   1,289      
Recurring [Member] | Call Options on Interest Rate Futures Purchase Contracts [Member] | Nonaffiliates [Member] | Level 2 [Member]                        
Assets:                        
Derivative assets             0   0      
Recurring [Member] | Call Options on Interest Rate Futures Purchase Contracts [Member] | Nonaffiliates [Member] | Level 3 [Member]                        
Assets:                        
Derivative assets             0   0      
Recurring [Member] | Put Options On Interest Rate Futures Purchase Contracts | Nonaffiliates [Member]                        
Assets:                        
Derivative assets             5,566   4,109      
Recurring [Member] | Put Options On Interest Rate Futures Purchase Contracts | Nonaffiliates [Member] | Level 1 [Member]                        
Assets:                        
Derivative assets             5,566   4,109      
Recurring [Member] | Put Options On Interest Rate Futures Purchase Contracts | Nonaffiliates [Member] | Level 2 [Member]                        
Assets:                        
Derivative assets             0   0      
Recurring [Member] | Put Options On Interest Rate Futures Purchase Contracts | Nonaffiliates [Member] | Level 3 [Member]                        
Assets:                        
Derivative assets             $ 0   $ 0      
[1] During the third quarter of 2026, the Company entered into an agreement to sell a portfolio of Agency MSRs with an aggregate UPB of approximately $10.0 billion. The transaction is expected to close in the fourth quarter of 2026.
[2] All hedging derivatives are interest rate derivatives that are used as economic hedges.