Intangible Assets and Goodwill - Changes in Carrying Amount of Franchise Assets and Goodwill (Detail) - USD ($) |
12 Months Ended | |
|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Indefinite-lived Intangible Assets [Line Items] | ||
| Net Goodwill, Beginning balance | $ 472,437,000 | $ 471,493,000 |
| Net Goodwill, Additions through current year acquisitions | 60,024,000 | |
| Net Goodwill, Reductions from dispositions | (5,737,000) | |
| Net Goodwill, Reductions from impairment | (900,000) | 0 |
| Net Goodwill, Prior year acquisition allocations | (44,000) | 944,000 |
| Net Goodwill, Ending balance | 525,780,000 | 472,437,000 |
| Franchise Assets [Member] | ||
| Indefinite-lived Intangible Assets [Line Items] | ||
| Franchise Assets, Beginning balance | 74,900,000 | 74,900,000 |
| Franchise Assets, Reductions from dispositions | (1,400,000) | |
| Franchise Assets, Reductions from impairment | (3,600,000) | |
| Franchise Assets, Ending balance | $ 69,900,000 | $ 74,900,000 |
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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of divestiture of an asset lacking physical substance and having a projected indefinite period of benefit to fair value. Excludes financial assets and goodwill. No definition available.
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- Details
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