Taxes on Income (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Taxes on Income [Abstract]
Tax benefit realized from equity compensation plans	$ 6,119,000	$ 3,001,000	$ 3,212,000
Operating loss carryforwards	515,000	5,699,000
Expiration dates, operating loss carryforwards	Dec. 31, 2030
Unrecognized tax benefits including interest and penalties	1,477,000
Amount that would impact the effective tax rate, if recognized	998,000
Income tax penalties and interest recognized	40,000	(421,000)	(43,000)
Accrued liabilities for payment of interest and penalties	$ 306,000	$ 266,000	$ 790,000
Minimum [Member] | State and Local Jurisdiction [Member]
Income Tax Examination [Line Items]
Years open to audit under the statute of limitations	2008
Minimum [Member] | Internal Revenue Service (IRS) [Member]
Income Tax Examination [Line Items]
Years open to audit under the statute of limitations	2011
Maximum [Member] | State and Local Jurisdiction [Member]
Income Tax Examination [Line Items]
Years open to audit under the statute of limitations	2013
Maximum [Member] | Internal Revenue Service (IRS) [Member]
Income Tax Examination [Line Items]
Years open to audit under the statute of limitations	2013