Long Term Liabilities (Details 1) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Long Term Debt Maturities 2012 [Member]
Long Term Debt Maturities	$ 0
Long Term Debt Maturities 2013 [Member]
Long Term Debt Maturities	0
Long Term Debt Maturities 2014 [Member]
Long Term Debt Maturities	0
Long Term Debt Maturities 2015 [Member]
Long Term Debt Maturities	100,000
Long Term Debt Maturities 2016 [Member]
Long Term Debt Maturities	405,000
Long Term Debt Maturities Beyond Five Years [Member]
Long Term Debt Maturities	$ 1,398,000