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The maximum principal balance of the variable funding note allowed, under the related party transaction.

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Amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The amount of cash or securities placed with a broker or counterparty as security for a trading or derivatives securities position which was partially obtained with funds provided by the broker dealer.

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The fair value, as of the date of each statement of financial position presented, of loans that are restricted as collateral for the payment of repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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The sum of the fair values, as of the date of each statement of financial position presented, of securities that are restricted as collateral for the payment of related debt obligations, primarily secured borrowings and repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Weighted average interest rate of short-term debt outstanding calculated over time.

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For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, average borrowings during the period.

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Short-Term Borrowings - Assets Sold Under Agreement to Repurchase (Details) - USD ($) $ in Thousands			12 Months Ended
	Apr. 28, 2021	Dec. 19, 2016	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Apr. 01, 2020
Carrying value:
Unpaid principal balance			$ 7,297,360
Total loans sold under agreements to repurchase			7,292,735	$ 9,654,797
Fair value of assets pledged to secure			8,629,861	10,912,178
Servicing advances			232,107	413,484
PennyMac Holdings, L L C Repurchase Agreement
Carrying value:
Related Party Transaction, Maximum Principal Balance of Variable Funding Note		$ 1,000,000
Fannie Mae Repurchase Agreement
Carrying value:
Related Party Transaction, Maximum Principal Balance of Variable Funding Note	$ 1,000,000
FMSR VFN Repurchase Agreement
Carrying value:
Related Party Transaction, Maximum Principal Balance of Variable Funding Note	$ 250,000
Note Payable
During the period:
Average balance of assets sold under agreements to repurchase			1,300,000	1,300,000	$ 1,300,000
Carrying value:
Amortization of debt issuance costs			2,200	1,800	1,800
Loan Repo Facility
During the period:
Average balance of assets sold under agreements to repurchase			$ 6,911,843	$ 3,348,928	$ 2,185,830
Weighted-average interest rate (as a percent)			2.09%	2.91%	3.74%
Total interest expense			$ 164,132	$ 112,778	$ 74,215
Maximum daily amount outstanding			10,969,029	9,663,995	4,141,680
Carrying value:
Unpaid principal balance			7,297,360	9,663,995
Unamortized debt issuance costs and premiums			(4,625)	(9,198)
Total loans sold under agreements to repurchase			$ 7,292,735	$ 9,654,797
Weighted average interest rate (as a percent)			1.83%	1.90%
Available borrowing capacity committed			$ 285,419	$ 372,803
Available borrowing capacity uncommitted			8,417,221	2,163,202
Available borrowing capacity			8,702,640	2,536,005
Margin deposits placed with counterparties			10,875	5,625
Amortization of premium			19,400	15,300	$ (7,500)
Loan Repo Facility \| Loans held for sale
Carrying value:
Fair value of assets pledged to secure			8,629,861	10,912,178
Loan Repo Facility \| Servicing advances
Carrying value:
Servicing advances			232,107	413,484
Loan Repo Facility \| Financing receivable \| PennyMac Mortgage Investment Trust
Carrying value:
Fair value of assets pledged to secure				80,862
Loan Repo Facility \| Deposits
Carrying value:
Fair value of assets pledged to secure			36,632	153,054
Loan Repo Facility \| Mortgage servicing rights
Carrying value:
Fair value of assets pledged to secure			$ 3,552,812	$ 2,490,267
PLS \| Credit Suisse First Boston Mortgage Capital LLC \| Note Payable
Mortgage loans sold under agreement to repurchase
Maximum loan amount						$ 600,000