Fair Value Fair Value (Narrative) (Details)	Dec. 31, 2012
Fair Value Disclosures [Abstract]
Fair value measurements with unobservable inputs, percent of total financial assets	6.00%
Fair value measurements with unobservable inputs, percent of total financial liabilities	2.00%
Percent of level 3 portfolio priced using non-binding broker quotes	97.00%
Percent of level 3 portfolio priced using internal model pricing	3.00%