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Reconciliation of Statutory Federal Income Tax (Benefit) Expense Reported in Net Income to Combined Actual Income Tax (Benefit) Expense (Parenthetical) (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014
Reconciliation of Provision of Income Taxes [Line Items] |  |
Income tax (benefit) expense, adjustment to deferred taxes | $ (1,400,000) | $ 600,000.0

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- Definition Reconciliation of Provision of Income Taxes [Line Items] + References No definition available. + Details
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- Definition Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32639-109319 + Details
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