CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) (Unaudited) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Restricted cash and cash equivalents	$ 5,825	$ 5,746
Purchases of property and equipment	54,354	$ 36,471
8.0 % Convertible Notes [Member]
Debt Instrument Interest Rate Stated Percentage		8.00%
Equity Method Investee [Member] \| Construction [Member]
Purchases of property and equipment	$ 3,914	$ 11,369

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

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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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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