Commitments and Contingencies (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) entities	Dec. 31, 2015 USD ($)
Loss Contingencies [Line Items]
Guaranteed Repayment of Economic Development Bonds	$ 32,900
Number of unconsolidated subsidiaries for which loans guaranteed | entities	1
Maximum Guarantee Exposure for Joint Venture Loans	$ 52,100
Total obligation for operating leases for certain land positions	43,400
Other Liabilities	114,569	$ 106,283
Special Tax Assessment [Member]
Loss Contingencies [Line Items]
Other Liabilities	10,200
Land [Member]
Loss Contingencies [Line Items]
Total obligation for operating leases for certain land positions	$ 311,100