Fair Value Measurement - Narrative (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)
Allowance for Loan and Lease Loss
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Valuation allowance, period increase (decrease)	$ 143
Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Discount on appraisals of secured collateral (as a percent)	10.00%
Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Discount on appraisals of secured collateral (as a percent)	50.00%