Cash Equivalents and Marketable Securities (Textual) (Details) (USD $)	Sep. 30, 2013 security	Dec. 31, 2012 security		Sep. 30, 2012	Dec. 31, 2011
Cash Equivalents and Marketable Securities [Abstract]
Cash and cash equivalents	$ 26,911,000	$ 32,003,000	[1]	$ 25,573,000	$ 25,762,000
Money market funds	21,100,000	24,800,000
Cash	$ 5,800,000	$ 7,200,000
Number of marketable securities in a loss position (securities)	0	0

[1] The Condensed Consolidated Balance Sheet as of December 31, 2012 has been derived from the audited consolidated financial statements as of that date, but does not include all disclosures including notes required by GAAP for complete financial statements.