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

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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- Definition

Carrying amount as of the balance sheet date of obligations due all related parties.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(3),(4))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.17)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Balance Type:	credit
Period Type:	instant

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

+ Details

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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.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Transactions with Related Parties - Management Fees - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Aug. 04, 2009
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	$ 120,000
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%
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%
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%
PMT agreed to reimburse PCM for a payment		$ 2,900,000
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
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
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%
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%
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%
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
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
PennyMac Financial Services, Inc. [Member]
Mortgage Loans on Real Estate [Line Items]
Performance incentive fee description	The performance incentive fee is calculated quarterly and is equal to: (a) 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 (b) 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 (c) 20% of the amount by which net income for the quarter exceeds a 16% return on equity plus the high watermark
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 PFSI, in each case during the 24-month period before termination.