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Summary of Significant Accounting Policies and Practices - Additional Information (Detail) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Significant Accounting Policies [Line Items] |  |  |
Maturity period of highly liquid investments | Three months or less |  |
Percentage of subsidiaries owned | 100.00% | 100.00% | 100.00%
Joint Venture [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Percentage of subsidiaries owned | 49.00% |  |
RFK [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Percentage of subsidiaries owned | 99.70% |  |

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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571 + Details
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