Basis and Summary of Significant Accounting Policies - Components of Prepaid Expenses and Other Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Prepaid Expenses	$ 38,692	$ 31,509
Prepaid Insurance	32,722	36,735
Assets Held for Sale	9,853	10,118
Deferred Tax Asset	7,556	11,589
Other Assets	28,741	26,548
Prepaid Expenses and Other Assets	$ 117,564	$ 116,499