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Summary of Significant Accounting Policies - Basis of Consolidation Policy Additional Information (Details) | 12 Months Ended
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Dec. 31, 2018
Maximum [Member] |
Basis of Consolidation [Abstract] |
Ownership interest to use equity method | 50.00%
Ownership interest to use cost method | 20.00%
Minimum [Member] |
Basis of Consolidation [Abstract] |
Ownership interest to be held for consolidation | 50.00%

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- Definition Basis of Consolidation [Abstract] + References No definition available. + Details
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- Definition Ownership Interest to be Held for Consolidation + References No definition available. + Details
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- Definition Entities in which the company has less than 20% investment and where they do not excercise significant influence are accounted for under the cost method. + References No definition available. + Details
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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details
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