CONSOLIDATED STATEMENTS OF OPERATIONS (Parenthetical) (USD $) In Thousands	12 Months Ended
Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
CONSOLIDATED STATEMENTS OF OPERATIONS
Interest Income	$ 1,787	$ 2,566	$ 5,485

Income derived from investments in debt securities and on cash and cash equivalents the earnings of which reflect the time value of money or transactions in which the payments are for the use or forbearance of money.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 14

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 7
-Article 5

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration