Parent Company Information - Condensed Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
ASSETS
Cash	$ 188,291				$ 155,289				$ 37,725
Total assets	10,204,017	$ 9,303,199	$ 8,398,376	$ 7,819,000	7,478,573	$ 6,992,530	$ 6,841,706	$ 6,902,891
LIABILITIES AND STOCKHOLDERS' EQUITY
Income taxes payable	504,569	480,559	441,336	414,636	400,546	74,158	67,357	58,956
Total liabilities	8,142,510	7,391,586	6,619,379	6,117,808	5,824,782	5,075,820	4,979,762	5,108,692
Total liabilities and stockholders' equity	10,204,017	9,303,199	8,398,376	7,819,000	7,478,573	6,992,530	6,841,706	6,902,891
Long-term debt	1,493,466	$ 1,500,647	$ 1,515,631	$ 1,752,817	1,648,973	$ 1,566,672	$ 1,473,188	$ 1,380,358
PennyMac Financial Services, Inc. | Parent Company
ASSETS
Cash	2,250
Investment in subsidiaries	2,443,407				1,975,231
Due from subsidiaries	100				582
Total assets	2,445,757				1,975,813
LIABILITIES AND STOCKHOLDERS' EQUITY
Payables to subsidiaries	4,194				575
Income taxes payable	380,056				321,447
Total liabilities	384,250				322,022
Stockholders' equity	2,061,507				1,653,791
Total liabilities and stockholders' equity	$ 2,445,757				$ 1,975,813