Business Combinations and Divestitures - Additional Information (Details)			3 Months Ended	9 Months Ended
	Sep. 23, 2020 USD ($) shares	Jul. 08, 2020 USD ($) client shares	Sep. 30, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jul. 09, 2020 USD ($)	Dec. 31, 2019 USD ($)
Business Acquisition [Line Items]
Loans			$ 4,852,911,000	$ 4,852,911,000		$ 4,194,512,000
Line of credit, maximum borrowing capacity			227,500,000	227,500,000
Goodwill			163,263,000	163,263,000		158,743,000
Factored receivables
Business Acquisition [Line Items]
Loans			1,016,337,000	1,016,337,000		$ 619,986,000
Over-Formula Advances | Factored receivables
Business Acquisition [Line Items]
Loans			62,200,000	62,200,000
Transport Financial Solutions
Business Acquisition [Line Items]
Cash paid		$ 108,375,000
Number of common stock (in shares) | shares		630,268
Stock consideration		$ 13,942,000
Number of large clients | client		3
Portion of purchase price returned (in shares) | shares	630,268
Elimination amount of contingent consideration	$ 9,900,000
Goodwill		$ 4,520,000
Cash due from seller subsequent to liquidation of stock consideration		17,196,000
Total consideration		105,121,000		19,248,000
Noninterest Income, Other				2,000,000.0
Intangible assets		$ 3,500,000
Intangible asset, estimated useful life		8 years
Indemnification asset		$ 31,218,000
Factored receivables acquired, contractual amount		45,228,000
Factored receivables acquired, fair value		44,962,000
Acquisition related costs			827,000
Transport Financial Solutions | Over-Formula Advances
Business Acquisition [Line Items]
Loans	$ 62,200,000				$ 62,200,000
Transport Financial Solutions | Over-Formula Advances | Factored receivables
Business Acquisition [Line Items]
Loans			$ 62,200,000	$ 62,200,000
Transport Financial Solutions | Indemnification Agreement
Business Acquisition [Line Items]
Percent indemnified, first $30 million of losses	100.00%
First increment of losses incurred	$ 30,000,000
Percent indemnified, second $30 million of losses	50.00%
Second increment of losses incurred	$ 30,000,000
Total indemnification amount	45,000,000
Net orderly liquidation value	60,000,000
Transport Financial Solutions | Indemnification Agreement | CVLG
Business Acquisition [Line Items]
Line of credit, maximum borrowing capacity	$ 45,000,000
Transport Financial Solutions | Maximum
Business Acquisition [Line Items]
Fair value of consideration paid included contingent consideration		$ 9,900,000