Fair Value Measurement (Schedule of Reconciliation of Assets and Liabilities Measured at Fair Value Using Significant Unobservable Inputs (Level 3) on a Recurring Basis) (Details) (USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Fair Value Measurement
Mortgage servicing rights, Beginning Balance	$ 15,605,000	$ 13,628,000	$ 14,454,000.000	$ 12,625,000.000
Mortgage servicing rights, Change included in earnings	(328,000)	(1,671,000)	(511,000.000)	(1,800,000.000)
Mortgage servicing rights, Purchases and issuances	1,073,000	938,000	2,407,000.000	2,070,000.000
Mortgage servicing rights, Ending Balance	16,350,000	12,895,000.000	16,350,000	12,895,000.000
Mortgage servicing rights, Net change in unrealized gains or (losses) relating to items held at end of period	(45,000)	(1,368,000)	79,000.000	(1,263,000.000)
Junior subordinated debentures, Beginning Balance	81,220,000	79,563,000	80,688,000.000	85,666,000.000
Junior subordinated debentures, Change included in earnings	1,523,000		3,033,000.000	(4,150,000.000)
Junior subordinated debentures, Sales and settlements	(977,000)	(957,000)	(1,955,000.000)	(1,926,000.000)
Junior subordinated debentures, Ending Balance	81,766,000	79,590,000.000	81,766,000	79,590,000.000
Junior subordinated debentures, Net change in unrealized gains or losses relating to items held at end of period	$ 1,523,000	$ 984,000	$ 3,033,000.000	$ (4,150,000.000)

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases And Issuances

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Period Type:	duration

- Definition

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Sales And Settlements

+ Details

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Period Type:	duration

- Details

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- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c(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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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- Definition

The increase (decrease) of assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period. Such increase (decrease) may be comprised of changes in fair value (gains or losses) whether realized or unrealized that have been included in earnings, changed net asset value, or other comprehensive income (a separate component of shareholders' equity); purchases, sales, issuances, or settlements of assets; and net transfers in to or out of this category within the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c(1), c(2), c(3)
-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 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

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- Definition

This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c
-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 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

+ References

+ Details

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- Definition

The increase (decrease) of liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period. Such increase (decrease) may be comprised of changes in fair value (gains or losses) whether realized or unrealized that have been included in earnings, changed net asset value, or other comprehensive income (a separate component of shareholders' equity); purchases, sales, issuances, or settlements of assets; and net transfers in to or out of this category within the fair value hierarchy.

+ References

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	na
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- Definition

This element represents a liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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