Carrying value as of the balance sheet date of payments made in excess of existing cash balances, which will be honored by the bank but reflected as a loan to the entity. Overdrafts generally have a very short time frame for correction or repayment and are therefore more similar to short-term bank financing than trade financing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 45
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99376301&loc=d3e1243-112600

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Credit Facilities and Long-Term Debt, Polish Overdraft Facility (Details) zł in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Mar. 31, 2018 PLN (zł)	Dec. 31, 2017 PLN (zł)
Line of Credit Facility [Line Items]
Overdraft facility	$ 5,800		zł 19,800
HSBC Bank Polaska S.A [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 8,800		zł 30,000
Overdraft facility expiration date	Dec. 31, 2018
Overdraft facility	$ 5,800		zł 19,800
HSBC Bank Polaska S.A [Member] \| 1M WIBOR [Member]
Line of Credit Facility [Line Items]
Basis spread on variable rate		0.75%