Derivative Financial Instruments - Other Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Derivative assets:
Derivative asset, before netting	$ 270,518		$ 270,518		$ 232,293
Netting	(89,876)		(89,876)		(119,217)
Total derivative assets	180,642		180,642		113,076
Derivative liabilities:
Derivative liability, before netting	170,411		170,411		102,881
Netting	(137,908)		(137,908)		(61,981)
Net amounts of liabilities presented in the consolidated balance sheet	32,503		32,503		40,900
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Gains (losses) recognized on derivative financial instruments	(109,102)	$ (171,777)	(2,328)	$ (466,422)
Interest rate lock commitments and loans held for sale
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Gains (losses) recognized on derivative financial instruments	(28,853)	52,955	(173,899)	105,192
Mortgage servicing rights
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Gains (losses) recognized on derivative financial instruments	(116,294)	(155,317)	(27,654)	(449,651)
Margin Deposits
Derivative assets:
Collateral placed with (received from) derivative counterparties	48,032		48,032		(57,236)
Interest rate lock commitments
Derivative assets:
Total derivative assets	143,061		143,061		56,946
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Gains (losses) recognized on derivative financial instruments	32,211	$ (1,055)	108,588	$ (20,841)
Forward contracts | Purchases
Derivative Instruments
Notional amount	13,037,927		13,037,927		12,760,764
Derivative assets:
Derivative asset, before netting	89,834		89,834		3,701
Derivative liabilities:
Derivative liability, before netting	174		174		66,646
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter			12,760,764
Balance at end of quarter	13,037,927		13,037,927
Forward contracts | Sales
Derivative Instruments
Notional amount	22,218,056		22,218,056		23,440,334
Derivative assets:
Derivative asset, before netting	2,939		2,939		152,526
Derivative liabilities:
Derivative liability, before netting	159,266		159,266		12,854
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter			23,440,334
Balance at end of quarter	22,218,056		22,218,056
Forward contracts | Sales | PennyMac Mortgage Investment Trust
Derivative Instruments
Notional amount	84,070		84,070
Derivative liabilities:
Derivative liability, before netting	1,038		1,038
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at end of quarter	84,070		84,070
MBS put options
Derivative Instruments
Notional amount	500,000		500,000		450,000
Derivative assets:
Derivative asset, before netting					3,278
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter			450,000
Balance at end of quarter	500,000		500,000
Put options on Eurodollar futures | Purchases
Derivative Instruments
Notional amount	7,000,000		7,000,000		4,270,000
Derivative assets:
Derivative asset, before netting	996		996		12,592
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter			4,270,000
Balance at end of quarter	7,000,000		7,000,000
Call options on Eurodollar futures | Purchases
Derivative Instruments
Notional amount	11,525,000		11,525,000		7,600,000
Derivative assets:
Derivative asset, before netting	33,688		33,688		3,250
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter			7,600,000
Balance at end of quarter	11,525,000		11,525,000
Call options on Eurodollar futures | Sales
Derivative Instruments
Notional amount	2,800,000		2,800,000
Derivative liabilities:
Derivative liability, before netting	10,063		10,063
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at end of quarter	2,800,000		2,800,000
Treasury future | Purchases
Derivative Instruments
Notional amount	5,998,000		5,998,000		7,467,000
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter			7,467,000
Balance at end of quarter	5,998,000		5,998,000
Treasury future | Sales
Derivative Instruments
Notional amount	7,347,000		7,347,000		10,521,000
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter			10,521,000
Balance at end of quarter	7,347,000		7,347,000
Not designated as hedging instrument | Interest rate lock commitments
Derivative Instruments
Notional amount	10,998,207		10,998,207		7,801,677
Derivative assets:
Derivative asset, before netting	143,061		143,061		56,946
Derivative liabilities:
Derivative liability, before netting	908		908		$ 23,381
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter			7,801,677
Balance at end of quarter	$ 10,998,207		$ 10,998,207