Deposits - Summary of Deposit Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Interest and Noninterest Bearing Domestic Deposit Liabilities To Deposit Liabilities [Abstract]
Noninterest-bearing demand	$ 1,510,224	$ 1,124,121
Interest-bearing checking	2,057,052	1,797,504
Money market	1,225,890	1,003,149
Savings	584,361	498,201
Certificates of deposit $250 thousand and under	895,056	652,144
Certificates of deposit over $250 thousand	183,200	218,660
Total deposits	$ 6,455,783	$ 5,293,779
Percentage Of Interest and Noninterest Bearing Domestic Deposit Liabilities To Deposit Liabilities [Abstract]
Noninterest-bearing demand	23.40%	21.20%
Interest-bearing checking	31.90%	34.00%
Money market	19.00%	19.00%
Savings	9.10%	9.40%
Certificates of deposit $250 thousand and under	13.80%	12.30%
Certificates of deposit over $250 thousand	2.80%	4.10%
Total deposits	100.00%	100.00%