Summary of Projections of Amortization Expense for Mortgage Servicing Rights (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Mortgage Servicing Rights [Line Items]
Year ended March 31, 2013	$ 8,566	$ 8,608
Estimate for the year ended March 31, 2014	4,847
2015	3,878
2016	3,102
2017	2,482
2018	1,985
Thereafter	7,941
Total	$ 24,235

Estimated amortization of mortgage servicing rights after year five.

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- Definition

Estimated amortization of mortgage servicing rights remainder of the fiscal.

+ References

No definition available.

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- Definition

Estimated amortization of mortgage servicing rights year five.

+ References

No definition available.

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- Definition

Estimated amortization of mortgage servicing rights year four.

+ References

No definition available.

+ Details

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- Definition

Estimated amortization of mortgage servicing rights year three.

+ References

No definition available.

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- Definition

Estimated amortization of mortgage servicing rights year two.

+ References

No definition available.

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- Definition

The periodic amortization (in proportion to and over the period of estimated net servicing income or loss) of capitalized servicing rights, which contractually entitle the servicer to receive fees and ancillary revenues for performing billing, collection, disbursement and recordkeeping services in connection with a mortgage portfolio. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 4

-Subparagraph (a)(4)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122739-111746

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 17

-Subparagraph g(1)(d)

-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

The value of new servicing assets, subsequently measured at amortized value, acquired or created during the current period through purchases or from transfers of financial assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 4

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122739-111746

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 17

-Subparagraph g(1)(b)

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

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS140-4/FIN46(R)-8

-Paragraph B10

-Subparagraph a(2)

-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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