Servicing Rights - Mortgage Servicing Assets (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance, beginning of period			$ 10,821
Additions for new MSR capitalized			1,639	$ 1,572
Changes in fair value:
Balance, end of period	$ 10,836		10,836
Balance of mortgage loans serviced for others	$ 598,415		$ 598,415		$ 557,583
MSR as a percentage of serviced loans	1.81%		1.81%		1.94%
Mortgage servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance, beginning of period	$ 11,254	$ 8,039	$ 10,821	7,305
Additions for new MSR capitalized	532	812	1,639	1,572
Changes in fair value:
Due to changes in model inputs of assumptions	(630)	110	(1,007)	365
Other	(320)	(228)	(617)	(509)
Balance, end of period	10,836	$ 8,733	10,836	$ 8,733
Balance of mortgage loans serviced for others	$ 598,415		$ 598,415		$ 557,583
MSR as a percentage of serviced loans	1.81%		1.81%		1.94%

Mortgage Loans Serviced for Third Party

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- Definition

Mortgage Servicing Rights, Percent of Loans Serviced

+ References

No definition available.

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- Definition

The value of new servicing assets, subsequently measured at fair value, acquired or created during the current period through purchases or from transfers of financial assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746

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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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- Definition

Amount of increase (decrease) in fair value from changes in the inputs used to calculate the fair value of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(4)(i)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746

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- References

No definition available.

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- Definition

Amount of increase (decrease) from changes in fair value classified as other for a contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(4)(ii)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746

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