Net Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Interest income:
Interest income	$ 128,478	$ 53,882
Interest expense:
Obligations under capital lease		15
Interest expense	131,771	77,307
Net interest expense	(3,293)	(23,425)
PennyMac Mortgage Investment Trust
Interest income:
Interest income	21
Non-affiliates
Interest income:
Cash and short-term investments	16,245	572
Loans held for sale at fair value	60,993	49,113
Placement fees relating to custodial funds	51,219	4,197
Interest expense:
Assets sold under agreements to repurchase	59,223	23,770
Mortgage loan participation purchase and sale agreements	2,923	1,120
Notes payable	40,778	9,909
Unsecured senior notes	23,428	23,428
Obligations under capital lease		15
Interest shortfall on repayments of mortgage loans serviced for Agency securitizations	3,210	17,479
Interest on mortgage loan impound deposits	1,967	1,586
Other	242
Interest expense	131,771	77,307
Loan Repo Facility
Interest expense:
Assets sold under agreements to repurchase	$ 59,223	$ 23,770