Parent Company Information - Condensed Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue
Repricing of payable to exchanged Private National Mortgage Acceptance Company, LLC unitholders under tax receivable agreement		$ 280	$ 379
Interest expense:
To non-affiliates	$ 389,419	263,133	201,688
Interest expense	390,699	271,551	211,979
Net interest income (expense)	(90,530)	(24,525)	76,721
Expenses
Professional services	94,283	64,064	32,859
Other	51,428	31,090	27,581
Total expenses	1,808,178	1,464,988	947,960
Income before provision for income taxes	1,359,183	2,240,609	529,444
Provision for income taxes	355,693	593,725	136,479
Net income	1,003,490	1,646,884	392,965
Private National Mortgage Acceptance Company [Member]
Revenue
Repricing of payable to exchanged Private National Mortgage Acceptance Company, LLC unitholders under tax receivable agreement		280	379
PennyMac Financial Services, Inc. | Parent Company [Member]
Revenue
Dividends from subsidiaries	982,740	602,606	36,376
Interest income from subsidiary	77,162	15,830
Interest expense:
To non-affiliates	70,208	8,774
To subsidiary		83	153
Interest expense	70,208	8,857	153
Net interest income (expense)	6,954	6,973	(153)
Total net revenue	989,694	609,579	36,223
Expenses
Charitable contributions	5,800	2,314
Professional services	2,236	42
Other	449	327
Total expenses	8,485	2,683
Income before provision for income taxes	981,209	606,896	36,223
Provision for income taxes	238,803	395,340	91,291
Income before equity in undistributed earnings of subsidiaries	742,406	211,556	(55,068)
Equity in undistributed earnings of subsidiaries	261,084	1,435,328	448,033
Net income	$ 1,003,490	$ 1,646,884	$ 392,965