Mortgage Banking Operations - Mortgage Repurchase Liability (Details) - Representations and warranties reserve for loan receivables [Member] - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Mortgage Repurchase Losses [Roll Forward]
Balance, beginning of period	$ 2,504	$ 2,990	$ 3,015	$ 3,382
Additions (reductions), net of adjustments	643	(338)	1,248	(370)
Realized losses	(273)	(148)	(1,389)	(508)
Balance, end of period	$ 2,874	$ 2,504	$ 2,874	$ 2,504

Amount of loss contingency liability.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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- Definition

Amount of cash outflow reducing loss contingency liability.

+ References

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- Definition

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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