Fair Value Measurements (Schedule of Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) (Recurring [Member], Level 3 [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	$ 10,514
Gains and losses (realized and unrealized): included in earnings	(2,780)	[1]
Gains and losses (realized and unrealized): Included in other comprehensive income	2,466
Purchases	0
Issuances	17,868
Sales	0
Settlements	(133)
Transfers into level 3	0
Transfers out of Level 3	0
Balance at end of period	8,407
Securities Available for Sale [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	843	[2]
Gains and losses (realized and unrealized): Included in earnings	(2,772)	[1],[2]
Gains and losses (realized and unrealized): Included in other comprehensive income	2,466	[2]
Purchases	0	[2]
Issuances	0	[2]
Sales	0	[2]
Settlements	(133)	[2]
Transfers into level 3	0	[2]
Transfers out of Level 3	0	[2]
Balance at end of period	404	[2]
Mortgage loans held for sale [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	9,813	[3]
Gains and losses (realized and unrealized): Included in earnings	(198)	[1],[3]
Gains and losses (realized and unrealized): Included in other comprehensive income	0	[3]
Purchases	0	[3]
Issuances	17,868	[3]
Sales	(19,528)	[3]
Settlements	0	[3]
Transfers into level 3	0	[3]
Transfers out of Level 3	0	[3]
Balance at end of period	7,955	[3]
Derivative Assets / Liabilities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	(142)	[4]
Gains and losses (realized and unrealized): included in earnings	190	[1],[4]
Gains and losses (realized and unrealized): Included in other comprehensive income	0	[4]
Purchases	0	[4]
Issuances	0	[4]
Sales	0	[4]
Settlements	0	[4]
Transfers into level 3	0	[4]
Transfers out of Level 3	0	[4]
Balance at end of period	$ 48	[4]

[1] Losses included in earnings for Level 3 securities available for sale were included in net impairment losses recognized in earnings in the Consolidated Income Statement. Losses included in earnings for Level 3 mortgage loans held for sale and derivative assets and liabilities were included in net gains on loan sales and commissions on loans originated for others in the Consolidated Statements of Income.

[2] Level 3 securities available for sale were comprised of pooled trust preferred debt securities in the form of collateralized debt obligations.

[3] Level 3 mortgage loans held for sale consisted of certain mortgage loans whose fair value was determined utilizing a discounted cash flow analysis.

[4] Level 3 derivative assets / liabilities consisted of forward loan commitments (interest rate lock commitments and commitments to sell residential real estate mortgages) whose fair value was determined utilizing a discounted cash flow analysis.