Other Non-Current Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Other Assets, Noncurrent [Abstract]
Advances made under EPC and non-EPC contracts	$ 14,000	$ 83,579
Advances made to municipalities for water system enhancements	95,584	89,953
Tax-related payments and receivables	29,351	31,712
Equity method investments	11,983	20,295
Other	100,540	88,916
Other non-current assets	$ 251,458	$ 314,455