Bank segment - Derivatives (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Not designated as a hedging instrument
Derivative instrument
Asset derivatives	$ 472		$ 91
Liability derivatives	171		43
Net gains (losses) recognized in the Statement of Income	253	$ 88
Interest rate lock commitments
Derivative instrument
Notional amount	31,406		10,180
Fair value	462		91
Interest rate lock commitments \| Not designated as a hedging instrument
Derivative instrument
Asset derivatives	463		91
Liability derivatives	1		0
Interest rate lock commitments \| Not designated as a hedging instrument \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	371	124
Forward commitments
Derivative instrument
Notional amount	34,165		10,132
Fair value	(161)		(43)
Forward commitments \| Not designated as a hedging instrument
Derivative instrument
Asset derivatives	9		0
Liability derivatives	170		$ 43
Forward commitments \| Not designated as a hedging instrument \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	$ (118)	$ (36)

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
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Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
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-Paragraph 10
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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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+ References

No definition available.

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