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

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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.

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Fair value, after offset of derivative asset, of financial liability or 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, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Bank segment - Derivatives (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Not designated as a hedging instrument
Derivative instrument
Asset derivatives	$ 0		$ 0		$ 137
Liability derivatives	0		0		30
Net gains (losses) recognized in the Statement of Income	(186)	$ (209)	(107)	$ (239)
Interest rate lock commitments
Derivative instrument
Notional amount	0		0		13,669
Fair value	0		0		131
Interest rate lock commitments \| Not designated as a hedging instrument
Derivative instrument
Asset derivatives	0		0		133
Liability derivatives	0		0		2
Interest rate lock commitments \| Not designated as a hedging instrument \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	(248)	(119)	(131)	(414)
Forward commitments
Derivative instrument
Notional amount	0		0		14,465
Fair value	0		0		(24)
Forward commitments \| Not designated as a hedging instrument
Derivative instrument
Asset derivatives	0		0		4
Liability derivatives	0		0		$ 28
Forward commitments \| Not designated as a hedging instrument \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	$ 62	$ (90)	$ 24	$ 175