Taxes on Income 4 (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Taxes [Abstract]
Beginning of the year	$ 15,837	$ 12,864	$ 7,210
Additions:
Tax positions taken in prior years	188	0	2,195
Tax positions taken in current years	3,354	3,146	3,459
Reductions:
Settlements	(791)	(173)	0
End of year	$ 18,588	$ 15,837	$ 12,864