Mortgage servicing rights - Schedule of Changes in Mortgage Servicing Rights (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Servicing Asset at Fair Value, Amount [Roll Forward]
Carrying value at beginning of period	$ 64,031	$ 93,160	$ 88,829	$ 76,107
Capitalization	11,212	16,304	19,932	29,814
Sales	0	0	(29,160)	0
Change in fair value:
Due to pay-offs/pay-downs	(3,305)	(2,207)	(5,100)	(5,267)
Due to change in valuation inputs or assumptions	(5,558)	2,192	(8,121)	8,795
Carrying value at period end	$ 66,380	$ 109,449	$ 66,380	$ 109,449

Servicing asset at fair value, changes in fair value due to pay-offs or pay-downs.

No definition available.

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- Definition

Amortized amount 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 4
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-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746

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-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122492-111745

+ Details

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- Definition

Amount of additions from purchases, assumption or transfer to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

+ Details

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- Definition

Amount conveyed to unrelated parties of contract to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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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, assumptions, or model used to calculate the fair value of the 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
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-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122625-111746

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- References

No definition available.

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