We are exposed to market risk from changes in foreign currency exchange rates, short-term interest rates and price fluctuations of certain material commodities such as copper. Market risks for changes in interest rates relate primarily to our debt obligations under our Amended Credit Agreement. Foreign currency exchange risks are attributable to sales to foreign customers and purchases from foreign suppliers not denominated in a location’s functional currency, foreign plant operations, intercompany indebtedness, intercompany investments and include exposures to the European Euro, Mexican Peso, Canadian Dollar, Hungarian Forint, Macedonian Denar, Ukrainian Hryvnia, Japanese Yen, Chinese Renminbi, Korean Won and Vietnamese Dong.

The Company regularly enters into derivative contracts with the objective of managing its financial and operational exposure arising from these risks by offsetting gains and losses on the underlying exposures with gains and losses on the financial instruments used to hedge them. The maximum length of time over which we hedge our exposure to foreign currency exchange risks is one year. We had foreign currency derivative contracts with a notional value of $23,473 and $33,250 outstanding as of June 30, 2019 and December 31, 2018, respectively.

The maximum length of time over which we hedge our exposure to price fluctuations in material commodities is two years. No commodity swap contracts were outstanding at June 30, 2019 or at December 31, 2018.

We do not enter into derivative financial instruments for speculative or trading purposes. Our hedging relationships are formally documented at the inception of the hedge, and hedges must be highly effective in offsetting changes to future cash flows on hedged transactions both at the inception of a hedge and on an ongoing basis to be designated for hedge accounting treatment. For derivative contracts which can be classified as a cash flow hedge, the effective portion of the change in the fair value of the derivative is recorded to accumulated other comprehensive loss in the consolidated balance sheet. When the underlying hedge transaction is realized, the gain or loss included in accumulated other comprehensive loss is recorded in earnings in the consolidated statements of income on the same line as the gain or loss on the hedged item attributable to the hedged risk. We record the ineffective portion of foreign currency hedging instruments, if any, to foreign currency gain (loss) in the consolidated statements of income. See Note 9 for the amount of unrealized loss associated with foreign currency derivatives previously reported in accumulated other comprehensive loss that was reclassified into earnings during 2019. Though we continuously monitor the hedging program, derivative positions and hedging strategies, foreign currency forward exchange agreements have not always been designated as hedging instruments for accounting purposes.

The Company uses an income approach to value derivative instruments, analyzing quoted market prices to calculate the forward values and then discounts such forward values to the present value using benchmark rates at commonly quoted intervals for the instrument’s full term.

Information related to the recurring fair value measurement of derivative instruments in our consolidated condensed balance sheet as of June 30, 2019 is as follows:

Asset Derivatives

Liability Derivatives

Net Asset/
(Liabilities)

Hedge

Designation

Fair Value

Hierarchy

Balance Sheet
Location

Fair
Value

Balance Sheet
Location

Fair
Value

Foreign currency derivatives

Cash flow hedge

Level 2

Current assets

1,155

Current liabilities

—

1,155

Information relating to the effect of derivative instruments on our consolidated condensed statements of income is as follows:

	Location	Three Months Ended June 30, 2019			Three Months Ended June 30, 2018			Six Months Ended June 30, 2019		Six Months Ended June 30, 2018
Foreign currency derivatives	Product revenues	$	435		$	(524	)	$	675	$	(605	)
	Selling, general and administrative	—			22				—		75
	Other comprehensive income		297		(1,561		)		1,063		551
	Foreign currency (loss) gain		(32	)	10				(69)		47
Total foreign currency derivatives		$	700		$	(2,053	)	$	1,669	$	68
Commodity derivatives	Cost of sales	$	—		$	—			—	$	145
	Other comprehensive income	—			—				—		(218	)
Total commodity derivatives		$	—		$	—		$$	—	$	(73)

We did not incur any hedge ineffectiveness during the three- and six-month periods ended June 30, 2019 and 2018.