Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands		3 Months Ended
	Jan. 01, 2020	Mar. 31, 2020	Mar. 31, 2019
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	$ 17,667	$ 17,667	$ 17,820
Initial PCD Allowance	2,800	2,786
Provision for credit losses on loans		8,600	364
Charge-offs		(713)	(661)
Recoveries		309	298
Balance, end of period	22,577	48,440	17,821
Impact of adopting ASC 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	19,791	19,791
Balance, end of period	17,667
Mortgage warehouse
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	1,077	1,077	1,006
Initial PCD Allowance		0
Provision for credit losses on loans		(22)	8
Charge-offs		0	0
Recoveries		0	0
Balance, end of period	0	1,055	1,014
Mortgage warehouse | Impact of adopting ASC 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	0	0
Balance, end of period	1,077
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	11,996	11,996	10,495
Initial PCD Allowance		2,786
Provision for credit losses on loans		6,916	1,122
Charge-offs		(69)	(77)
Recoveries		89	16
Balance, end of period		32,550	11,556
Commercial | Impact of adopting ASC 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	10,832	10,832
Real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	923	923	1,676
Initial PCD Allowance		0
Provision for credit losses on loans		700	(115)
Charge-offs		(26)	0
Recoveries		9	27
Balance, end of period		5,654	1,588
Real estate | Impact of adopting ASC 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	4,048	4,048
Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	3,671	3,671	4,643
Initial PCD Allowance		0
Provision for credit losses on loans		1,006	(651)
Charge-offs		(618)	(584)
Recoveries		211	255
Balance, end of period		9,181	$ 3,663
Consumer | Impact of adopting ASC 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	$ 4,911	$ 4,911