Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Segment Information
Interest income	$ 60,417	$ 39,674
Interest expense	22,064	15,543
Net interest income	38,353	24,131
Provision for loan losses	2,998	649
Net Interest Income After Provision for Loan Losses	35,355	23,482
Noninterest income	19,902	3,664
Noninterest expense	22,293	13,035
Income Before Income Taxes	32,964	14,111
Income taxes	8,381	3,541
Net Income	24,583	10,570
Total assets	7,908,398	3,976,725	$ 6,371,928
Other
Segment Information
Interest income	668	471
Interest expense	(1,828)	(968)
Net interest income	2,496	1,439
Net Interest Income After Provision for Loan Losses	2,496	1,439
Noninterest income	(921)	(663)
Noninterest expense	3,238	2,602
Income Before Income Taxes	(1,663)	(1,826)
Income taxes	(460)	(507)
Net Income	(1,203)	(1,319)
Total assets	41,453	37,993
Multifamily | Operating Segments
Segment Information
Interest income	420	331
Net interest income	420	331
Net Interest Income After Provision for Loan Losses	420	331
Noninterest income	17,364	2,691
Noninterest expense	10,348	3,977
Income Before Income Taxes	7,436	(955)
Income taxes	2,037	(243)
Net Income	5,399	(712)
Total assets	180,772	160,609
Mortgage Warehousing | Operating Segments
Segment Information
Interest income	30,099	14,380
Interest expense	12,085	7,529
Net interest income	18,014	6,851
Provision for loan losses	1,180	133
Net Interest Income After Provision for Loan Losses	16,834	6,718
Noninterest income	2,776	753
Noninterest expense	3,019	2,336
Income Before Income Taxes	16,591	5,135
Income taxes	4,154	1,303
Net Income	12,437	3,832
Total assets	4,362,423	1,554,233
Banking | Operating Segments
Segment Information
Interest income	29,230	24,492
Interest expense	11,807	8,982
Net interest income	17,423	15,510
Provision for loan losses	1,818	516
Net Interest Income After Provision for Loan Losses	15,605	14,994
Noninterest income	683	883
Noninterest expense	5,688	4,120
Income Before Income Taxes	10,600	11,757
Income taxes	2,650	2,988
Net Income	7,950	8,769
Total assets	$ 3,323,750	$ 2,223,890