Fair Value Measurement (Details 1) (USD $)	6 Months Ended	12 Months Ended
Jun. 30, 2012	Dec. 31, 2011
Other asset-backed securities
Market Value	$ 85,281,000	$ 102,771,000
Other asset-backed securities [Member]
Other asset-backed securities
Market Value	26,697,000	24,232,000
Level 3 [Member] \| Other asset-backed securities [Member]
Other asset-backed securities
Market Value	26,697,000	24,232,000
Net Average Price	6.16	5.49
Alt-A [Member] \| Level 3 [Member] \| Other asset-backed securities [Member]
Other asset-backed securities
Unobservable Input	Price	Price
Pricing Source	Third-party pricing service	Third-party pricing service
Market Value	151,000	210,000
Net Average Price	12.90	14.57
Home Equity [Member] \| Level 3 [Member] \| Other asset-backed securities [Member]
Other asset-backed securities
Unobservable Input	Price	Price
Pricing Source	Third-party pricing service	Third-party pricing service
Market Value	199,000	185,000
Net Average Price	39.99	23.35
Bank Loans and Trust Preferred [Member] \| Level 3 [Member] \| Other asset-backed securities [Member]
Other asset-backed securities
Unobservable Input	Price	Price
Pricing Source	Broker	Broker
Market Value	5,000	4,000
Net Average Price	0.01	0.01
Direct Exposure to Subprime [Member] \| Level 3 [Member] \| Other asset-backed securities [Member]
Other asset-backed securities
Unobservable Input	Price	Price
Pricing Source	Third-party pricing service	Third-party pricing service
Market Value	38,000	61,000
Net Average Price	0.89	0.86
Indirect Exposure - High Grade [Member] \| Level 3 [Member] \| Other asset-backed securities [Member]
Other asset-backed securities
Unobservable Input	Discount margin	Discount margin
Pricing Source	Manual	Manual
Market Value	3,849,000	3,776,000
Net Average Price	3.20	3.14
Indirect Exposure - Mezzanine [Member] \| Level 3 [Member] \| Other asset-backed securities [Member]
Other asset-backed securities
Unobservable Input	Price	Price
Pricing Source	Broker	Broker
Market Value	15,671,000	13,010,000
Net Average Price	6.95	5.63
Other [Member] \| Level 3 [Member] \| Other asset-backed securities [Member]
Other asset-backed securities
Unobservable Input	Discount margin	Discount margin
Pricing Source	Manual	Manual
Market Value	6,784,000	6,986,000
Net Average Price	$ 36.41	$ 37.5

- 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. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

+ References+ Details