Interest-Bearing Deposits by Type (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Interest-bearing deposits by type
Interest-bearing demand deposits	$ 377,445	$ 353,321
Money market deposits	240,101	237,257
Savings deposits	273,221	263,019
Individual retirement accounts	125,552	126,658
Certificates of deposit	675,260	706,568
Total	$ 1,691,579	$ 1,686,823

The aggregate of all domestic and foreign interest-bearing deposit liabilities.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.12)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 9

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- Definition

Amount of interest-bearing domestic certificate of deposit liabilities.

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Amount of money in interest-bearing domestic accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits.

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Amount of interest-bearing domestic money market demand account deposit liabilities.

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Amount of interest-bearing domestic deposit liabilities for time deposit liabilities other than certificates of deposit.

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Amount of interest-bearing domestic savings deposit liabilities. Saving deposits bear interest and have no stated maturity.

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