6. Goodwill and Indefinite-Lived Intangible Assets (Tables) |
12 Months Ended | |||||||||||||||||||||||||
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Dec. 31, 2017 | ||||||||||||||||||||||||||
| Goodwill and Intangible Assets Disclosure [Abstract] | ||||||||||||||||||||||||||
| Reconciliation of Change in Carrying Value of Goodwill |
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- References No definition available.
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- Definition Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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