Cash and Cash Equivalents, Restricted Cash and Marketable Securities (Details Textual) - USD ($) |
6 Months Ended | |||
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Jun. 30, 2017 |
Jun. 30, 2016 |
Dec. 31, 2016 |
Oct. 31, 2010 |
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| Cash And Cash Equivalents [Abstract] | ||||
| Restricted cash | $ 135,265,000 | $ 113,139,000 | ||
| Line Of Credit Facility, Maximum Borrowing Capacity | 1,800,000,000 | $ 1,800,000,000 | ||
| Realized gains or losses on the sale of marketable securities | $ 0 | $ 0 | ||
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- References No definition available.
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This item represents the total realized gain (loss) included in earnings for the period as a result of selling marketable securities categorized as trading, available-for-sale, or held-to-maturity. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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