Securities with Gross Unrealized Losses in Continuous Loss Position (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Available for sale, Less Than 12 Months Gross Unrealized Losses	$ 4,343	$ 740
Available for sale, Less Than 12 Months Fair Value	149,200	72,507
Available for sale, Over 12 Months Gross Unrealized Losses	466	69
Available for sale, Over 12 Months Fair Value	4,417	1,684
Held to maturity, Less Than 12 Months Gross Unrealized Losses	11,499
Held to maturity, Less Than 12 Months Fair Value	249,891
Held to maturity, Over 12 Months Gross Unrealized Losses	994
Held to maturity, Over 12 Months Fair Value	26,535
Marketable Securities, Less Than 12 Months Gross Unrealized Losses	15,842
Marketable Securities, Less Than 12 Months Fair Value	399,091
Marketable Securities, Over 12 Months Gross Unrealized Losses	1,460
Marketable Securities, Over 12 Months Fair Value	30,952
Government sponsored residential mortgage-backed securities
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Available for sale, Less Than 12 Months Gross Unrealized Losses	3,717	631
Available for sale, Less Than 12 Months Fair Value	118,846	49,081
Available for sale, Over 12 Months Gross Unrealized Losses	311
Available for sale, Over 12 Months Fair Value	2,761
Held to maturity, Less Than 12 Months Gross Unrealized Losses	5,866
Held to maturity, Less Than 12 Months Fair Value	145,438
Held to maturity, Over 12 Months Gross Unrealized Losses	953
Held to maturity, Over 12 Months Fair Value	24,729
U.S. government guaranteed mortgage-backed securities
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Available for sale, Less Than 12 Months Gross Unrealized Losses	137
Available for sale, Less Than 12 Months Fair Value	15,045
Held to maturity, Less Than 12 Months Gross Unrealized Losses	1,391
Held to maturity, Less Than 12 Months Fair Value	38,314
Corporate bonds
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Available for sale, Less Than 12 Months Gross Unrealized Losses	93	63
Available for sale, Less Than 12 Months Fair Value	4,659	4,330
Available for sale, Over 12 Months Gross Unrealized Losses
Available for sale, Over 12 Months Fair Value
Held to maturity, Less Than 12 Months Gross Unrealized Losses	567
Held to maturity, Less Than 12 Months Fair Value	22,059
State and municipal bonds
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Available for sale, Less Than 12 Months Gross Unrealized Losses	2	9
Available for sale, Less Than 12 Months Fair Value	256	1,178
Available for sale, Over 12 Months Gross Unrealized Losses
Available for sale, Over 12 Months Fair Value
Held to maturity, Less Than 12 Months Gross Unrealized Losses	345
Held to maturity, Less Than 12 Months Fair Value	5,852
Government sponsored enterprise obligations
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Available for sale, Less Than 12 Months Gross Unrealized Losses	310	37
Available for sale, Less Than 12 Months Fair Value	7,189	17,918
Available for sale, Over 12 Months Gross Unrealized Losses
Available for sale, Over 12 Months Fair Value
Held to maturity, Less Than 12 Months Gross Unrealized Losses	3,330
Held to maturity, Less Than 12 Months Fair Value	38,228
Held to maturity, Over 12 Months Gross Unrealized Losses	41
Held to maturity, Over 12 Months Fair Value	1,806
Mutual funds
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Available for sale, Less Than 12 Months Gross Unrealized Losses	84
Available for sale, Less Than 12 Months Fair Value	3,205
Available for sale, Over 12 Months Gross Unrealized Losses	155	69
Available for sale, Over 12 Months Fair Value	$ 1,656	$ 1,684

This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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