CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Purchases of property and equipment	$ (86,131)	$ (56,808)
Restricted cash and cash equivalents	$ 5,599	0
8.0 % Convertible Notes [Member]
Debt instrument, interest rate, stated percentage	8.00%
Consolidated Construction Joint Venture [Member] \| Joint Venture Consolidated [Member]
Purchases of property and equipment	$ 15,040	$ 13,537

Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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