Stockholders' Equity (Details) (Non-employee director [Member], USD $) In Thousands, except Share data, unless otherwise specified	1 Months Ended	12 Months Ended
Jul. 31, 2012	Feb. 29, 2012	Jul. 31, 2011	Feb. 28, 2011	Jul. 31, 2010	Feb. 28, 2010	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Non-employee director [Member]
Stock granted to our non-employee directors
Number of Shares	16,328	31,820	25,632	51,642	34,425	53,844	48,148	77,274	88,269
Fair Value per Share	$ 8.36	$ 6.60	$ 5.54	$ 4.11	$ 3.66	$ 3.15
Fair Value of Grant	$ 136	$ 210	$ 142	$ 212	$ 126	$ 169	$ 346	$ 354	$ 295

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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