Net Interest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Interest income:
Interest income	$ 294,062	$ 300,169	$ 247,026
Interest expense:
Obligations under capital lease	20	169	425
Interest expense	335,427	390,699	271,551
Net interest expense	(41,365)	(90,530)	(24,525)
PennyMac Mortgage Investment Trust
Interest income:
Interest income		387	3,325
Interest expense:
Interest expense		1,280	8,418
Non-affiliates
Interest income:
Cash and short-term investments	19,839	3,280	6,154
Loans held for sale at fair value	172,124	275,176	184,789
Placement fees relating to custodial funds	102,099	21,326	52,758
Interest income	294,062	299,782	243,701
Interest expense:
Mortgage loan participation purchase and sale agreements	7,314	4,153	4,933
Obligations under capital lease	20	169	425
Notes payable	79,813	39,782	46,222
Unsecured senior notes	95,014	70,208	8,774
Corporate revolving line of credit			1,537
Interest shortfall on repayments of mortgage loans serviced for Agency securitizations	40,741	105,430	82,285
Interest on mortgage loan impound deposits	7,066	5,545	6,179
Other	335,427	389,419	263,133
Loan Repo Facility
Interest expense:
Assets sold under agreements to repurchase	105,459	164,132	112,778
Loan Repo Facility | Non-affiliates
Interest expense:
Assets sold under agreements to repurchase	$ 105,459	$ 164,132	$ 112,778