Commitments and Contingent Liabilities - Summary of Contract or Notional Amount of Outstanding Loan and Lease Commitments (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Commitments And Contingencies Liabilities [Line Items]
Fixed Rate	$ 64,214	$ 56,576
Variable Rate	978,344	973,896
Total	1,042,558	1,030,472
Commitments to Extend Credit
Commitments And Contingencies Liabilities [Line Items]
Fixed Rate	63,524	55,852
Variable Rate	920,694	908,382
Total	984,218	964,234
Letters of Credit
Commitments And Contingencies Liabilities [Line Items]
Fixed Rate	690	724
Variable Rate	57,650	65,514
Total	$ 58,340	$ 66,238