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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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- References

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- Definition

Amount before tax, after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

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Amount of tax expense (benefit), after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount before tax, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount of tax (expense) benefit, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended									9 Months Ended		12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Consolidated Statements of Comprehensive Income [Abstract]
Net Earnings	$ 3,559	$ 15,370	$ 11,477	$ 15,328	$ 4,439	$ 13,196	$ (951)	$ 14,817	$ 5,026	$ (2,989)	$ 31,244	$ 46,614	$ 32,088	$ 50,651
Other Comprehensive Income (Loss):
Foreign currency translation adjustments	9,033		381							25,073	4,380	109	(12,520)	(10,112)
Pension and retiree medical benefits	379		23							541	61	(2,248)	4,121	(5,382)
Cash Flow Hedge	(1,732)		35							(6,311)	(394)	(305)	164	0
Income Taxes:
Foreign currency translation adjustments	0		10							0	15	32	25	13
Pension and retiree medical benefits	(138)		(9)							(160)	(23)	504	(1,265)	1,859
Cash Flow Hedge	646		(13)							2,354	147	114	(61)	0
Total Other Comprehensive Loss, net of tax	8,188		427							21,497	4,186	(1,794)	(9,536)	(13,622)
Comprehensive Income	$ 11,747		$ 11,904							$ 18,508	$ 35,430	$ 44,820	$ 22,552	$ 37,029