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Segments (Notes) | 12 Months Ended
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Dec. 31, 2017
Segment Reporting [Abstract] |
Segments | Segments Our chief operating decision maker reviews financial information presented on a consolidated basis for purposes of allocating resources and evaluating financial performance. There are no segment managers who are held accountable by the chief operating decision maker, or anyone else, for operations, operating results and planning for levels or components below the consolidated unit level. Accordingly, we determined we have one operating and reportable segment. During the years ended December 31, 2017, 2016 and 2015, 92.1%, 93.8% and 94.3% of our revenue, respectively, and substantially all of our long-lived assets were attributable to operations in the United States.

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- Definition The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -URI http://asc.fasb.org/topic&trid=2134510 + Details
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