Segments (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($) segment	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Segments and Related Information
Number of segments | segment	3
Revenues:
Net gains on loans held for sale at fair value	$ 104,385	$ 298,459
Loan origination fees	31,390	67,858
Fulfillment fees from PennyMac Mortgage Investment Trust	11,923	16,754
Net loan servicing fees	148,837	286,309
Net interest income (expense):
Interest income	128,478	53,882
Interest expense, before non-segment activities	131,771	77,307
Net interest expense, before non-segment activities	(3,293)	(23,425)
Management fees from PennyMac Mortgage Investment Trust	7,257	8,117
Other	2,363	3,432
Total net revenues, before non-segment activities	302,862	657,504
Expenses	264,715	422,984
Income before provision for income taxes	38,147	234,520
Assets:
Segment assets at quarter end	20,103,185		$ 16,822,584
PennyMac Mortgage Investment Trust
Revenues:
Net gains on loans held for sale at fair value	(485)	(9,652)
Net interest income (expense):
Interest income	21
Operating segment
Assets:
Segment assets at quarter end	20,103,185	14,617,902
Operating segment | Investment management
Net interest income (expense):
Management fees from PennyMac Mortgage Investment Trust	7,257	8,117
Other	2,012	2,031
Total net revenues, before non-segment activities	9,269	10,148
Expenses	8,929	10,051
Income before provision for income taxes	340	97
Assets:
Segment assets at quarter end	25,300	22,646
Operating segment | Mortgage banking
Revenues:
Net gains on loans held for sale at fair value	104,385	298,459
Loan origination fees	31,390	67,858
Fulfillment fees from PennyMac Mortgage Investment Trust	11,923	16,754
Net loan servicing fees	148,837	286,309
Net interest income (expense):
Interest income	128,478	53,882
Interest expense, before non-segment activities	131,771	77,307
Net interest expense, before non-segment activities	(3,293)	(23,425)
Other	351	1,401
Total net revenues, before non-segment activities	293,593	647,356
Expenses	255,786	412,933
Income before provision for income taxes	37,807	234,423
Assets:
Segment assets at quarter end	20,077,885	14,595,256
Operating segment | Mortgage banking Production
Revenues:
Net gains on loans held for sale at fair value	74,726	221,610
Loan origination fees	31,390	67,858
Fulfillment fees from PennyMac Mortgage Investment Trust	11,923	16,754
Net interest income (expense):
Interest income	56,993	30,941
Interest expense, before non-segment activities	54,083	27,059
Net interest expense, before non-segment activities	2,910	3,882
Other	574	785
Total net revenues, before non-segment activities	121,523	310,889
Expenses	141,163	301,619
Income before provision for income taxes	(19,640)	9,270
Assets:
Segment assets at quarter end	7,543,466	4,905,974
Operating segment | Mortgage banking Servicing
Revenues:
Net gains on loans held for sale at fair value	29,659	76,849
Net loan servicing fees	148,837	286,309
Net interest income (expense):
Interest income	71,485	22,941
Interest expense, before non-segment activities	77,688	50,248
Net interest expense, before non-segment activities	(6,203)	(27,307)
Other	(223)	616
Total net revenues, before non-segment activities	172,070	336,467
Expenses	114,623	111,314
Income before provision for income taxes	57,447	225,153
Assets:
Segment assets at quarter end	$ 12,534,419	$ 9,689,282