SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Impact of error on the income statement
Inventories, net	$ 127,295	$ 112,305	$ 97,381
Accrued expenses (taxes)		17,547	20,426
Material costs	296,193	270,210	248,667
Personnel costs	335,328	321,529	282,417
Other operating expenses	188,868	177,910	165,158
Income from operations	129,338	115,955	80,470
Income before taxes	98,169	84,134	34,535
Provision for income taxes	34,477	29,657	13,639
Net income	63,692	54,477	20,896
Basic Per Common Share Net Income (in dollars per share)	$ 1.86	$ 1.62	$ 0.65
Diluted Per Common Share Net Income (in dollars per share)	$ 1.83	$ 1.59	$ 0.64
As Previously Reported
Impact of error on the income statement
Inventories, net		114,086	98,290
Accrued expenses (taxes)		18,247	20,796
Material costs		267,677	247,565
Personnel costs		322,765	284,095
Other operating expenses		178,335	163,673
Income from operations		116,827	81,379
Income before taxes		85,006	35,444
Provision for income taxes		29,987	14,009
Net income		$ 55,019	$ 21,435
Basic Per Common Share Net Income (in dollars per share)		$ 1.64	$ 0.66
Diluted Per Common Share Net Income (in dollars per share)		$ 1.61	$ 0.65