Targeted and Actual Weighted Average Asset Allocations by Plan Asset Category (Detail)	Dec. 31, 2011	Dec. 31, 2010
Defined Benefit Plan Disclosure [Line Items]
Total	100.00%	100.00%
Targeted Range 70 to 80 percent
Defined Benefit Plan Disclosure [Line Items]
Equity securities	74.00%	72.00%
Bancorp common stock	2.00%	2.00%
Total equity securities	76.00%	74.00%
Targeted Range 20 to 25 Percent
Defined Benefit Plan Disclosure [Line Items]
Total fixed income securities	21.00%	23.00%
Targeted Range 0 to 5 Percent
Defined Benefit Plan Disclosure [Line Items]
Cash	3.00%	3.00%

The percentage of cash and cash equivalents to the fair value of total plan assets held as of the measurement date.

No definition available.

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- Definition

The percentage of the fair value of equity securities (including the Bancorp's common stock) to the fair value of total plan assets held as of the measurement date.

+ References

No definition available.

+ Details

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- Definition

The percentage of the fair value of Bancorp common stock to the fair value of total plan assets held as of the measurement date.

+ References

No definition available.

+ Details

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- Definition

The percentage of the fair value of debt securities to the fair value of total plan assets held as of the measurement date.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph d(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e2446-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

+ Details

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- Details

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- Definition

The percentage of the fair value of equity securities to the fair value of total plan assets held as of the measurement date.

+ References

+ Details

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- Definition

The aggregate percentage of the fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of total plan assets held as of the measurement date.

+ References

+ Details

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