Summary of Deposits (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Mar. 31, 2012
Deposits [Line Items]
Non-interest-bearing checking	0.00%	0.00%
Interest-bearing checking	0.08%	0.08%
Total checking accounts	0.04%	0.04%
Money market accounts	0.19%	0.30%
Regular savings	0.10%	0.10%
Advance payments by borrowers for taxes and insurance	0.10%	0.10%
Certificate of deposit, Weighted Average Rate	0.72%	1.31%
Total deposits, Weighted Average Rate	0.31%	0.65%
Non-interest-bearing checking	$ 267,732	$ 264,700
Interest-bearing checking	295,478	274,414
Total checking accounts	563,210	539,114
Money market accounts	491,330	468,283
Regular savings	290,705	265,238
Advance payments by borrowers for taxes and insurance	20,804	22,359
Certificates of deposit, Carrying Amount	658,976	969,907
Total deposits	2,025,025	2,264,901
0.00% to 0.99%
Deposits [Line Items]
Certificate of deposit, Weighted Average Rate	0.39%	0.59%
Certificates of deposit, Carrying Amount	519,909	487,026
0.00% to 0.99% \| Maximum
Deposits [Line Items]
Percentage of interest on certificates of deposit	0.99%
0.00% to 0.99% \| Minimum
Deposits [Line Items]
Percentage of interest on certificates of deposit	0.00%
1.00% to 1.99%
Deposits [Line Items]
Certificate of deposit, Weighted Average Rate	1.23%	1.37%
Certificates of deposit, Carrying Amount	92,164	264,300
1.00% to 1.99% \| Maximum
Deposits [Line Items]
Percentage of interest on certificates of deposit	1.99%
1.00% to 1.99% \| Minimum
Deposits [Line Items]
Percentage of interest on certificates of deposit	1.00%
2.00% to 2.99%
Deposits [Line Items]
Certificate of deposit, Weighted Average Rate	2.37%	2.24%
Certificates of deposit, Carrying Amount	17,628	154,993
2.00% to 2.99% \| Maximum
Deposits [Line Items]
Percentage of interest on certificates of deposit	2.99%
2.00% to 2.99% \| Minimum
Deposits [Line Items]
Percentage of interest on certificates of deposit	2.00%
3.00% to 3.99%
Deposits [Line Items]
Certificate of deposit, Weighted Average Rate	3.58%	3.52%
Certificates of deposit, Carrying Amount	12,433	24,462
3.00% to 3.99% \| Maximum
Deposits [Line Items]
Percentage of interest on certificates of deposit	3.99%
3.00% to 3.99% \| Minimum
Deposits [Line Items]
Percentage of interest on certificates of deposit	3.00%
4.00% and above
Deposits [Line Items]
Certificate of deposit, Weighted Average Rate	4.38%	4.89%
Certificates of deposit, Carrying Amount	$ 16,842	$ 39,126
4.00% and above \| Minimum
Deposits [Line Items]
Percentage of interest on certificates of deposit	4.00%

Advance payments by borrowers for taxes and insurance at weighted average.

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- Definition

Interest bearing checking at weighted average.

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- Definition

Net checking accounts at carrying amount.

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Net checking accounts at weighted average.

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- Definition

Non-interest-bearing checking Weighted average.

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- Definition

Regular savings carrying amount.

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Regular savings weighted average.

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- Definition

Carrying amount of accumulated prepayments received by financial institutions from borrowers for taxes (for example, property taxes) and insurance (for example, property and catastrophe) which will periodically be remitted to the appropriate governmental agency or vendor on behalf of the borrower.

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- Definition

A savings certificate entitling the Entity (that is, bearer) to receive interest at an established maturity date, based upon a fixed interest rate. A certificate of deposit may be issued in any denomination. Certificates of deposit are generally issued by commercial banks and, therefore, insured by the FDIC (up to the prescribed limit). Certificates of deposit generally restrict holders from withdrawing funds on demand without the incurrence of penalties. Generally, only certificates of deposit with original maturities of three months or less qualify as cash equivalents. Original maturity means original maturity to the entity holding the investment. As a related example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 1

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 8, 9

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.1)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Paragraph 37, 38, 39

-IssueDate 2006-05-01

-Chapter 13

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Amount of interest-bearing domestic checking deposit liabilities.

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- Definition

Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 8, 9

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Amount of noninterest-bearing domestic checking deposit liabilities.

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- Definition

Percentage of interest-bearing domestic certificates of deposit liabilities to total deposit liabilities.

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The weighted average interest rate for domestic certificates of deposit liabilities.

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The weighted average interest rate for domestic money market demand account deposit liabilities.

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The weighted average interest rate for domestic time deposit liabilities.

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