Fair Value Disclosures (Fair Value Assets and Liabilities Measured on Recurring Basis) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Inputs, Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Insurance deposit	$ 14,359	$ 13,059
Total assets	14,359	13,059
Fair Value, Inputs, Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total assets	0	0
Derivative interest rate contracts (Note 8)	(11,439)	(4,044)
Total liabilities	$ (11,439)	$ (4,044)