DERIVATIVE FINANCIAL INSTRUMENTS: Derivative Financial Instruments Level 4 (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair Value
Derivative Asset, Fair Value, Gross Asset	$ 2,576	$ 4,639
Derivative Asset, Fair Value, Gross Liability	(2,171)	(984)
Derivative Asset, Fair Value, Amount Offset Against Collateral	405	3,655
Derivative Liability, Fair Value, Gross Liability	3,017	1,912
Derivative Liability, Fair Value, Gross Asset	(2,171)	(938)
Derivative Liability, Fair Value, Amount Offset Against Collateral	846	974
Derivative Liability, Collateral, Right to Reclaim Cash, Offset		45
Derivatives in a net liability position	3,000
Collateral Already Posted, Aggregate Fair Value	1,400
Additional Collateral, Aggregate Fair Value	6,700
Other current assets \| Financial Swaps
Fair Value
Derivative Asset, Fair Value, Gross Asset	2,426	4,639
Derivative Asset, Fair Value, Gross Liability	(2,034)	(984)
Derivative Asset, Fair Value, Amount Offset Against Collateral	392	3,655
Derivative Liability, Fair Value, Gross Liability	2,034	938
Derivative Liability, Fair Value, Gross Asset	(2,034)	(938)
Derivative Liability, Fair Value, Amount Offset Against Collateral	0	0
Other current assets \| Forward contracts
Fair Value
Derivative Asset, Fair Value, Gross Asset	13
Derivative Asset, Fair Value, Gross Liability	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	13
Other current liabilities \| Financial Swaps
Fair Value
Derivative Asset, Fair Value, Gross Asset	134	0
Derivative Asset, Fair Value, Gross Liability	(134)	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	0	0
Derivative Liability, Fair Value, Gross Liability	924	806
Derivative Liability, Fair Value, Gross Asset	(134)	0
Derivative Liability, Fair Value, Amount Offset Against Collateral	790	806
Other current liabilities \| Forward contracts
Fair Value
Derivative Asset, Fair Value, Gross Asset	0
Derivative Asset, Fair Value, Gross Liability	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	0
Derivative Liability, Fair Value, Gross Liability	32	104
Derivative Liability, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Amount Offset Against Collateral	32	104
Other liabilities \| Financial Swaps
Fair Value
Derivative Asset, Fair Value, Gross Asset		0
Derivative Asset, Fair Value, Gross Liability		0
Derivative Asset, Fair Value, Amount Offset Against Collateral		0
Derivative Liability, Fair Value, Gross Liability		64
Derivative Liability, Fair Value, Gross Asset		0
Derivative Liability, Fair Value, Amount Offset Against Collateral		$ 64
Other assets \| Financial Swaps
Fair Value
Derivative Asset, Fair Value, Gross Asset	3
Derivative Asset, Fair Value, Gross Liability	(3)
Derivative Asset, Fair Value, Amount Offset Against Collateral	0
Derivative Liability, Fair Value, Gross Liability	27
Derivative Liability, Fair Value, Gross Asset	(3)
Derivative Liability, Fair Value, Amount Offset Against Collateral	$ 24

The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

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The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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Fair value of liability associated with 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.

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Fair value, before effects of master netting arrangements, of a 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. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after effects of master netting arrangements, 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 offset against an obligation to return collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, before effects of master netting arrangements, of a 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. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value of asset associated with 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.

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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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