Unaudited Supplemental Pro Forma Information (Detail) - Spectrum Inc. $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2017 USD ($) $ / shares
Business Acquisition [Line Items]
Total revenue \| $	$ 121,301
Net income \| $	$ 14,994
Earnings per share:
Basic \| $ / shares	$ 0.36
Diluted \| $ / shares	$ 0.36

Business Acquisition, Pro Forma, Earnings Per Share [Abstract]

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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.

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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