Restricted Stock Units Issued (Detail) (Restricted Stock, USD $)	3 Months Ended
Mar. 31, 2014
Restricted Stock
Restricted Stock Units
Beginning Restricted Stock Units	14,903
Restricted Stock Units Granted
Dividend Equivalents Earned	163
Restricted Stock Units Settled
Ending Restricted Stock Units	15,066
Weighted-Average Stock Price
Beginning Restricted Stock Units	$ 28.90
Restricted Stock Units Granted
Dividend Equivalents Earned	$ 31.48
Restricted Stock Units Settled
Ending Restricted Stock Units	$ 28.93

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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)(2)(iii)(1)

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

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