Represents the shareholders' equity levels upon which base management fee rates are based effective February 1, 2013.

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Mortgage-backed security yield average number of year.

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Represents a threshold return on shareholders' equity as defined before performance incentive fees are chargeable to the Company.

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Represents the net income expressed as a percentage of shareholders' equity upon which performance incentive fees are based.

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No definition available.

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Represents the maximum percentage of performance incentive fee payable in shares of the Company's common stock.

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Represents the net income expressed as a percentage of shareholders' equity upon which performance incentive fees are based.

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Represents the base management fee rate based on shareholders' equity as defined that existed before February 1, 2013.

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No definition available.

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Description of the fee payable by the company in the event of termination of the management agreement.

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No definition available.

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- Definition

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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Description of the nature of the payments to managing member or general partner for incentive rights held including the fee rate, basis of calculation, relevant accounting period, whether the fee is paid to an entity other than the managing member or general partner, or if the fee is waived.

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Indicates type of investment. Includes, but is not limited to, common stock, preferred stock, convertible security, fixed income security, government security, option purchased, warrant, loan participation and assignment, commercial paper, bankers' acceptance, certificates of deposit, short-term security, repurchase agreement, and other investment company.

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Amount of liabilities classified as other.

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Transactions with Related Parties - Management Fees - Additional Information (Detail) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Mortgage Loans On Real Estate [Line Items]
MBS yield, average number of year		30 years
Investment, Type [Extensible Enumeration]	Federal National Mortgage Association Certificates and Obligations (FNMA) [Member]	Federal National Mortgage Association Certificates and Obligations (FNMA) [Member]
Termination fees, description		The termination fee is equal to three times the sum of (a) the average annual base management fee, and (b) the average annual performance incentive fee earned by PCM, in each case during the 24-month period before termination of the management agreement.
PNMAC Capital Management LLC [Member]
Mortgage Loans On Real Estate [Line Items]
Percentage of change in net income due to quarterly adjustments		8.00%
PMT agreed to reimburse PCM for a payment	$ 165,000	$ 165,000
PNMAC Capital Management LLC [Member] \| 1.5% per annum of stockholders equity [Member]
Mortgage Loans On Real Estate [Line Items]
Base management fee annual rate	1.50%
PNMAC Capital Management LLC [Member] \| 1.375% per annum of stockholders equity [Member]
Mortgage Loans On Real Estate [Line Items]
Base management fee annual rate		1.375%
PNMAC Capital Management LLC [Member] \| 1.25% per annum of stockholders equity [Member]
Mortgage Loans On Real Estate [Line Items]
Base management fee annual rate		1.25%
PNMAC Capital Management LLC [Member] \| Net income exceeds 10% [Member]
Mortgage Loans On Real Estate [Line Items]
Percentage of net income for calculation of performance incentive fees		10.00%
Percentage of return on equity	12.00%	12.00%
PNMAC Capital Management LLC [Member] \| Net income exceeds 15% [Member]
Mortgage Loans On Real Estate [Line Items]
Percentage of net income for calculation of performance incentive fees		15.00%
Percentage of return on equity	16.00%	16.00%
PNMAC Capital Management LLC [Member] \| Net income exceeds 20% [Member]
Mortgage Loans On Real Estate [Line Items]
Percentage of net income for calculation of performance incentive fees		20.00%
PNMAC Capital Management LLC [Member] \| Maximum [Member]
Mortgage Loans On Real Estate [Line Items]
Percentage of performance incentive fee paid in Company's common shares		50.00%
PNMAC Capital Management LLC [Member] \| Maximum [Member] \| 1.5% per annum of stockholders equity [Member]
Mortgage Loans On Real Estate [Line Items]
Base management fee shareholders' equity limit	$ 2,000,000,000	$ 2,000,000,000
PNMAC Capital Management LLC [Member] \| Maximum [Member] \| 1.375% per annum of stockholders equity [Member]
Mortgage Loans On Real Estate [Line Items]
Base management fee shareholders' equity limit	$ 5,000,000,000	$ 5,000,000,000
PNMAC Capital Management LLC [Member] \| Maximum [Member] \| Net income exceeds 10% [Member]
Mortgage Loans On Real Estate [Line Items]
Percentage of return on equity	8.00%	8.00%
PNMAC Capital Management LLC [Member] \| Maximum [Member] \| Net income exceeds 15% [Member]
Mortgage Loans On Real Estate [Line Items]
Percentage of return on equity	12.00%	12.00%
PNMAC Capital Management LLC [Member] \| Maximum [Member] \| Net income exceeds 20% [Member]
Mortgage Loans On Real Estate [Line Items]
Percentage of return on equity	16.00%	16.00%
PNMAC Capital Management LLC [Member] \| Minimum [Member] \| 1.375% per annum of stockholders equity [Member]
Mortgage Loans On Real Estate [Line Items]
Base management fee shareholders' equity limit	$ 2,000,000,000	$ 2,000,000,000
PNMAC Capital Management LLC [Member] \| Minimum [Member] \| 1.25% per annum of stockholders equity [Member]
Mortgage Loans On Real Estate [Line Items]
Base management fee shareholders' equity limit	5,000,000,000	$ 5,000,000,000
PennyMac Financial Services, Inc. [Member]
Mortgage Loans On Real Estate [Line Items]
Performance incentive fee description		The performance incentive fee is equal to the sum of: •10% of the amount by which “net income” for the quarter exceeds (i) an 8% return on “equity” plus the “high watermark”, up to (ii) a 12% return on “equity”; plus •15% of the amount by which “net income” for the quarter exceeds (i) a 12% return on “equity” plus the “high watermark”, up to (ii) a 16% return on “equity”; plus 20% of the amount by which “net income” for the quarter exceeds a 16% return on “equity” plus the “high watermark.”
PMT agreed to reimburse PCM for a payment	$ 29,413,000	$ 29,413,000	$ 29,262,000