Condensed Consolidated Statements of Cash Flows (Unaudited) (Parenthetical) (USD $) In Thousands	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Cash flow from financing activities:
Senior notes, offering expenses	$ 350	$ 400
Common shares, issuance cost	$ 686	$ 524

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 95-13

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