Fair Value of Financial Instruments (Fair Value Measurements for Level 3 Instruments) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	$ 0	$ 8,118
Total realized and unrealized gains (losses):
Included in net income	0	0
Included in other comprehensive income	0	897
Purchases, sales, issuances and settlements, net	0	0
Transfers into (out of) Level 3	0	(9,015)
Balance at end of period	0	0
Amount of total gains (losses) for the period included in net income attributable to the change in unrealized gains (losses) relating to assets still held at the end of period	0	0
Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	2,718	1,647
Total realized and unrealized gains (losses):
Included in net income	1,481	(7)
Included in comprehensive income	0	0
Purchases, sales, issuances and settlements, net	(126)	(17)
Transfers into (out of) Level 3	0	0
Balance at end of period	4,073	1,623
Amount of total gains (losses) for the period included in net income attributable to the change in unrealized gains (losses) relating to assets still held at end of period	1,551	30
Debt Securities, Available for Sale [Member]
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	0	0
Total realized and unrealized gains (losses):
Included in net income	0	0
Included in other comprehensive income	0	0
Purchases, sales, issuances and settlements, net	0	0
Transfers into (out of) Level 3	0	0
Balance at end of period	0	0
Amount of total gains (losses) for the period included in net income attributable to the change in unrealized gains (losses) relating to assets still held at the end of period	0	0
Equity Securities, Available for Sale [Member]
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	0	8,118
Total realized and unrealized gains (losses):
Included in net income	0	0
Included in other comprehensive income	0	897
Purchases, sales, issuances and settlements, net	0	0
Transfers into (out of) Level 3	0	(9,015)
Balance at end of period	0	0
Amount of total gains (losses) for the period included in net income attributable to the change in unrealized gains (losses) relating to assets still held at the end of period	$ 0	$ 0

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+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

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

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

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Amount of purchases, sales, issues, and settlements (net) which have taken place in relation to assets measured at fair value on a recurring basis using unobservable inputs (level 3).

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-Name Accounting Standards Codification

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

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

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