Loans Receivable, Net - Aging of Recorded Investment in Past Due Loans Excluding PCI Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Financing Receivable, Past Due [Line Items]
Total Past Due	$ 38,505	$ 26,636
Greater than 90 Days Past Due	23,479	9,286
Loans Not Past Due	8,339,784	6,174,751
Total loans	8,378,289	6,201,387
30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due	5,428	11,231
60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due	9,598	6,119
Commercial and Industrial
Financing Receivable, Past Due [Line Items]
Total Past Due	2,553	307
Greater than 90 Days Past Due	2,246	207
Loans Not Past Due	908,209	395,784
Total loans	910,762	396,091
Commercial and Industrial | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due	307	100
Commercial and Industrial | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due	0	0
Commercial real estate – owner occupied
Financing Receivable, Past Due [Line Items]
Total Past Due	3,328	3,784
Greater than 90 Days Past Due	2,392	1,040
Loans Not Past Due	1,196,414	788,157
Total loans	1,199,742	791,941
Commercial real estate – owner occupied | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due	793	1,541
Commercial real estate – owner occupied | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due	143	1,203
Commercial real estate – investor
Financing Receivable, Past Due [Line Items]
Total Past Due	14,156	4,111
Greater than 90 Days Past Due	10,299	2,792
Loans Not Past Due	3,435,004	2,280,587
Total loans	3,449,160	2,284,698
Commercial real estate – investor | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due	1,857	381
Commercial real estate – investor | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due	2,000	938
Residential real estate
Financing Receivable, Past Due [Line Items]
Total Past Due	12,094	14,507
Greater than 90 Days Past Due	4,032	2,859
Loans Not Past Due	2,414,183	2,306,314
Total loans	2,426,277	2,320,821
Residential real estate | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due	943	8,161
Residential real estate | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due	7,119	3,487
Consumer
Financing Receivable, Past Due [Line Items]
Total Past Due	6,374	3,927
Greater than 90 Days Past Due	4,510	2,388
Loans Not Past Due	385,974	403,909
Total loans	392,348	407,836
Consumer | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due	1,528	1,048
Consumer | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due	$ 336	$ 491