Mortgage Servicing Rights - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Other Noninterest Income
Servicing Assets at Fair Value [Line Items]
Mortgage servicing fees	$ 1,600	$ 997	$ 4,000	$ 3,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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