Fair Value (Reconciliation of all Assets Measured at Fair Value on Recurring Basis, Using Significant Unobservable Inputs (Level 3)) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Obligations of State and Political Subdivisions [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Balance of Recurring Level 3 Assets at December 31	$ 12,169	$ 4,772
Total Gains or Losses (realized/unrealized) Included in Earnings	(21)	0
Maturities / Calls	(420)	(697)
Purchases	0	0
Balance of Recurring Level 3 Assets at March 31	11,728	4,075
Equity Securities [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Balance of Recurring Level 3 Assets at December 31	353	353
Total Gains or Losses (realized/unrealized) Included in Earnings	0	0
Maturities / Calls	0	0
Purchases	0	0
Balance of Recurring Level 3 Assets at March 31	353	353
Corporate Securities
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Balance of Recurring Level 3 Assets at December 31	0	1,005
Total Gains or Losses (realized/unrealized) Included in Earnings	0	0
Maturities / Calls	0	(1,005)
Purchases	0	0
Balance of Recurring Level 3 Assets at March 31	$ 0	$ 0

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Calls, Maturities, Paydowns.

No definition available.

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- Details

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- Definition

Amount of gain (loss) recognized in earnings, arising from assets measured at fair value on a recurring basis using unobservable inputs (level 3).

+ References

+ Details

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- Definition

Purchases that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

+ Details

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Balance Type:	debit
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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 Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

Reference 2: 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.

+ Details

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