Fair Value - Loans Held For Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans held for sale	$ 21,630	$ 18,526
Aggregate fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans held for sale	21,630	18,526
Contractual principal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans held for sale	20,869	17,822
Difference
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans held for sale	$ 761	$ 704