Stock Benefit Plans (Detail)	6 Months Ended
Jun. 30, 2013
Number of Equity Incentive Plans (in plans)	2
Employee Stock [Member] \| Restricted Stock [Member]
Non-Option Equity Instruments, Granted (in shares)	15,000
Director [Member] \| Restricted Stock [Member]
Non-Option Equity Instruments, Granted (in shares)	17,320

Net number of non-option equity instruments granted to participants.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration