Loans - Summary of Amortized Cost Basis of Collateral-dependent Loans by Class of Loans and Collateral Type (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	$ 5,028,058	$ 2,746,321
Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	20,634
Equipment and Machinery [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	4,010
Inventory and Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	1,285
Vehicles [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	404
Collateral Pledged [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	26,333
Real Estate Loans [Member] | Real Estate [Member] | Residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	1,505
Real Estate Loans [Member] | Real Estate [Member] | Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	18,688
Real Estate Loans [Member] | Collateral Pledged [Member] | Residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	1,505
Real Estate Loans [Member] | Collateral Pledged [Member] | Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	18,688
Other Loans [Member] | Real Estate [Member] | Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	440
Other Loans [Member] | Real Estate [Member] | Home Equity and Improvement [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	1
Other Loans [Member] | Equipment and Machinery [Member] | Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	4,010
Other Loans [Member] | Inventory and Receivables [Member] | Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	1,285
Other Loans [Member] | Vehicles [Member] | Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	332
Other Loans [Member] | Vehicles [Member] | Consumer Finance [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	72
Other Loans [Member] | Collateral Pledged [Member] | Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	6,067
Other Loans [Member] | Collateral Pledged [Member] | Home Equity and Improvement [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	1
Other Loans [Member] | Collateral Pledged [Member] | Consumer Finance [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net amount	$ 72