Financial instruments

Foreign currency forward contracts

The Company uses derivative instruments for risk management purposes. Foreign currency forward contracts designated as cash flows hedges are used to manage foreign currency transaction exposure. Foreign currency forward contracts not designated as hedges for accounting purposes are used to manage exposure related to near term foreign currency denominated monetary assets and liabilities. The Company enters into the non-designated foreign currency forward contracts for periods consistent with its currency translation exposures, which generally approximate one month. For the years ended December 31, 2018 and 2017, the Company recognized losses related to non-designated foreign currency forward contracts of $1.9 million and $2.6 million, respectively.

The total notional amount for all open foreign currency forward contracts designated as cash flow hedges as of December 31, 2018 and 2017 was $115.3 million and $88.5 million, respectively. The total notional amount for all open non-designated foreign currency forward contracts as of December 31, 2018 and 2017 was $125.9 million and $110.6 million, respectively. All open foreign currency forward contracts as of December 31, 2018 have durations of twelve months or less.

Cross-currency interest rate swaps

On October 4, 2018, the Company entered into cross-currency swap agreements with six different financial institution counterparties to hedge against the effect of variability in the U.S. dollar to euro exchange rate. Under the terms of the cross-currency swap agreements, the Company has notionally exchanged $500 million at an annual interest rate of 4.625% for €433.9 million at an annual interest rate of 1.942%. The swap agreements are designated as net investment hedges and expire on October 4, 2023. The cross-currency swaps are marked to market at each reporting date and any changes in fair value are recognized as a component of Accumulated other comprehensive income (loss) ("AOCI"). For the year ended December 31, 2018, the Company recognized foreign exchange gain of $4.0 million in foreign currency translation adjustments within AOCI related to the cross-currency swaps.

Balance sheet presentation

The following table presents the locations in the consolidated balance sheets and fair value of derivative instruments as of December 31, 2018 and 2017:



	December 31, 2018		December 31, 2017
	Fair Value
	(Dollars in thousands)
Asset derivatives:
Designated foreign currency forward contracts	$	1,216	$	914
Non-designated foreign currency forward contracts	106		307
Cross-currency interest rate swap	14,728		—
Prepaid expenses and other current assets	16,050		1,221
Total asset derivatives	16,050		1,221
Liability derivatives:
Designated foreign currency forward contracts	524		1,373
Non-designated foreign currency forward contracts	264		53
Other current liabilities	788		1,426
Cross-currency interest rate swap	7,793		—
Other liabilities	7,793		—
Total liability derivatives	$	8,581	$	1,426

See Note 12 for information on the location and amount of gains and losses attributable to derivatives that were reclassified from AOCI to expense (income), net of tax.

For the years ended December 31, 2018, 2017 and 2016, there was no ineffectiveness related to the Company’s hedging derivatives.

Concentration of Credit Risk

Concentrations of credit risk with respect to trade accounts receivable are generally limited due to the Company’s large number of customers located in many geographic areas. However, a portion of the Company’s trade accounts receivable outside the United States include sales to government-owned or supported healthcare systems in several countries which are subject to payment delays. Payment is dependent upon the creditworthiness of the healthcare systems in those countries and the financial stability of the countries' economies.

Certain of the Company’s customers, particularly in Greece, Italy, Portugal and Spain, have extended or delayed payments for products and services already provided, raising collectability concerns regarding the Company’s accounts receivable from these customers. As a result, the Company continues to closely monitor the allowance for doubtful accounts with respect to these customers. The following table provides information regarding the Company's allowance for doubtful accounts, the aggregate net current and long-term trade accounts receivable related to customers in Greece, Italy, Spain and Portugal and the percentage of the Company’s total net current and long-term trade accounts receivable represented by these customers' trade accounts receivable at December 31, 2018 and 2017:



	December 31, 2018			December 31, 2017
	(Dollars in thousands)
Allowance for doubtful accounts ₍₁₎	$	9,348		$	10,255
Current and long-term trade accounts receivable in Greece, Italy, Spain and Portugal ₍₂₎	$	39,026		$	49,054
Percentage of total net current and long-term trade accounts receivables	11.0		%	14.6		%

(1) The current portion of the allowance for doubtful accounts was $4.4 million and $3.5 million as of December 31, 2018 and 2017, respectively, and was recognized in accounts receivable, net.

(2) The long-term portion of trade accounts receivable, net from customers in Greece, Italy, Spain and Portugal at December 31, 2018 and 2017 was $2.7 million and $3.3 million, respectively. In December 2018, the Company sold $12.7 million of receivables outstanding with publicly funded hospitals in Italy and Portugal for $12.6 million.

For the years ended December 31, 2018, 2017 and 2016, net revenues from customers in Greece, Italy, Spain and Portugal were $142.7 million, $129.4 million and $125.3 million, respectively.