Segments (Schedule of net sales, adjusted EBITDA and certain other measures by reportable segment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Segment Reporting Information [Line Items]
Net sales	$ 314,653	$ 246,492	$ 563,379	$ 434,431
Gross profit	71,510	55,054	125,300	98,485
Depreciation & Amortization	3,067	3,031	6,026	6,061
Total Assets	349,950	298,299	349,950	298,299	286,012
Operating Segments [Member] | Geographic divisions [Member]
Segment Reporting Information [Line Items]
Net sales	302,666	237,212	541,183	418,020
Gross profit	69,085	52,929	120,618	94,872
Depreciation & Amortization	2,925	2,583	5,548	5,148
Adjusted EBITDA	14,788	7,669	19,372	6,668
Total Assets	320,500	272,865	320,500	272,865
Operating Segments [Member] | Other [Member]
Segment Reporting Information [Line Items]
Net sales	11,987	9,280	22,196	16,411
Gross profit	2,425	2,125	4,682	3,613
Depreciation & Amortization	33	32	65	65
Adjusted EBITDA	397	494	824	373
Total Assets	8,309	5,630	8,309	5,630
Other reconciling items [Member]
Segment Reporting Information [Line Items]
Net sales	0	0	0	0
Gross profit	0	0	0	0
Depreciation & Amortization	109	416	413	848
Adjusted EBITDA	(6,159)	(5,851)	(12,391)	(12,386)
Total Assets	$ 21,141	$ 19,804	$ 21,141	$ 19,804