Loans Held-for-Sale - Schedule of Loans Receivable Held-for-Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-for-sale	$ 357,755	$ 465,328
Residential mortgage loans at fair value
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-for-sale	269,140	252,712
SBA
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-for-sale	13,615	12,616
Indirect automobile
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-for-sale	$ 75,000	$ 200,000