Accrued Interest and Penalties on Unrecognized Tax Benefits (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)
Income Tax Disclosure [Abstract]
Interest related to unrecognized tax benefits	$ 860
Interest Included in Other Liabilities on the Consolidated Balance Sheets	$ 860

Amount of interest expense accrued for an underpayment of income taxes.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant