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Income Taxes - Schedule of Reconciliation of Gross Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	8 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015	Apr. 30, 2014
Income Tax Disclosure [Abstract]
Unrecognized tax benefits at beginning of period	$ 3,061	$ 3,073	$ 3,879
Gross increases for tax positions of prior years	14	168	22
Gross decreases for tax positions of prior years	(1)	(1)	(229)
Reductions resulting from lapse of statute of limitations	(1)	(409)	(611)
Gross increases resulting from reversal of benefit from lapse of statute of limitations		716
Settlements		(168)
Unrecognized tax benefits at end of period	$ 3,073	$ 3,379	$ 3,061

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- Definition

Unrecognized tax benefits increase resulting from lapse of applicable statute of limitations.

+ References

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Unrecognized Tax Benefit
-URI http://asc.fasb.org/extlink&oid=6527854

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
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-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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-SubTopic 10
-Section 50
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