Fair Value Measurements (Details Textual) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2011
Fair Value Measurements (Textuals) [Abstract]
Reclassification of accumulated other comprehensive income as a component of loss on early retirement of debt		$ 2,760
Number of swap agreements used for hedging interest payments		2
Interest Rate Swap [Member] \| Loss on early retirement of debt [Member]
Fair Value Measurements (Textuals) [Abstract]
Reclassification of accumulated other comprehensive income as a component of loss on early retirement of debt	$ 2,760	$ 2,760

The amount of net gains (losses) on a cash flow hedge reclassified in the period to earnings from accumulated other comprehensive income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 45
-Subparagraph b(1)

Name:	us-gaap_CashFlowHedgeGainLossReclassifiedToEarningsNet
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration