Fair Value Measurements (Fair Value of Assets on a Nonrecurring Basis) (Details) (Fair Value Measurements Nonrecurring [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	$ 65,267	$ 70,163	$ 84,146
Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	0	0	0
Significant Other Observable Inputs (Level 2) [Member]
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	0	0	0
Significant Unobservable Inputs (Level 3) [Member]
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	65,267	70,163	84,146
Impaired originated loans [Member]
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	47,073	51,694	58,202
Impaired originated loans [Member] | Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	0	0	0
Impaired originated loans [Member] | Significant Other Observable Inputs (Level 2) [Member]
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	0	0	0
Impaired originated loans [Member] | Significant Unobservable Inputs (Level 3) [Member]
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	47,073	51,694	58,202
Other real estate/repossessed assets [Member]
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	18,194	18,469	25,944
Other real estate/repossessed assets [Member] | Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	0	0	0
Other real estate/repossessed assets [Member] | Significant Other Observable Inputs (Level 2) [Member]
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	0	0	0
Other real estate/repossessed assets [Member] | Significant Unobservable Inputs (Level 3) [Member]
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	$ 18,194	$ 18,469	$ 25,944