Changes in Carrying Amount of Goodwill (Parenthetical) (Detail)	12 Months Ended
Dec. 31, 2015
Maximum
Goodwill [Line Items]
Preliminary purchase price allocation period	1 year

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.

Name:	us-gaap_GoodwillLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration