Commitments and Contingencies Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2015	Jan. 05, 2018	Dec. 31, 2016	Jun. 23, 2015
Line of Credit Facility, Maximum Borrowing Capacity				$ 500,000		$ 500,000
Warranty charge			$ 29,400
Insurance Recoveries		$ 8,000
Credit Facility [Member]
Line of Credit Facility, Remaining Borrowing Capacity	[1]	218,119			$ 203,897
Line of Credit Facility, Maximum Borrowing Capacity	[1]	$ 500,000			$ 500,000

[1] Refer to Note 6 and Note 19 for details regarding our secured credit facilities, including the refinancing of the 2015 credit facility.