Commitments, Off-Balance Sheet Arrangements and Contingent Liabilities (Details Textuals) (USD $)	3 Months Ended
Mar. 31, 2012	Dec. 31, 2011
Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Textuals) [Abstract]
Standby letters of credit Fair value	$ 3,583,000	$ 3,648,000
Carrying value of investments	36,000,000
Commitments under unconsolidated projects	17,000,000	15,000,000
Remaining receivable in the escrow amount	2,000,000
Residential mortgage loans sold with recourse risk	65,000,000	56,000,000
Residential mortgage loans sold with credit recourse risk	431,000,000	475,000,000
Reinsurance treaties minimum limit to assume liability for losses as percentage of aggregate risk exposure	5.00%
Reinsurance treaties maximum limit to assume liability for losses as percentage of aggregate risk exposure	10.00%
Corporations potential risk exposure	19,000,000
Corporations liability for reinsurance losses	9,000,000	8,000,000
Reserve for Off-balance Sheet Activities [Member]
Loss Contingencies [Line Items]
Loss contingency reserve	16,000,000	15,000,000
Indemnification Agreement [Member]
Loss Contingencies [Line Items]
Loss contingency reserve	$ 2,000,000

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Commitments under unconsolidated projects.

+ References

No definition available.

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- Definition

Liability For Reinsurance Losses.

+ References

No definition available.

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- Definition

Reinsurance treaties Maximum limit to assume liability for losses as percentage of aggregate risk exposure.

+ References

No definition available.

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- Definition

Reinsurance treaties Minimum limit to assume liability for losses as percentage of aggregate risk exposure.

+ References

No definition available.

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- Definition

Residential mortgage loans sold with credit recourse risk.

+ References

No definition available.

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- Definition

Residential mortgage loans sold with recourse risk.

+ References

No definition available.

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- Definition

Reflects the maximum amount of loss due to credit risk that, based on the gross fair value of the financial instrument, the entity would incur if parties to the financial instruments that make up the concentration failed completely to perform according to the terms of the contracts and the collateral or other security, if any, for the amount due proved to be of no value to the entity.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 15A

-Subparagraph 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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (b)

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. Fair value of lines of credit at the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Line-of-Credit Arrangement

-URI http://asc.fasb.org/extlink&oid=6517033

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- Definition

The carrying amount as of the balance sheet date of the combined total of loss contingency liabilities.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 9, 10, 11, 12

-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 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14326-108349

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- Definition

The carrying amount as of the balance sheet date of a recorded receivable related to a loss contingency accrual. For example, an insurance recovery receivable to the extent that the insurance recovery is probable and does not exceed the amount of the loss previously recognized in the financial statements.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12053-110248

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- Definition

Other investments not otherwise specified in the taxonomy.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(f,g))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 12

-Article 5

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 7

-Section 03

-Paragraph 1

-Subparagraph g

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

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

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