Variable Interest Entities ("VIE's") (CLN Structures Summary Information ) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014 item
Credit Linked Note Structure December 2006 [Member]
Credit Linked Notes Structures Summary Information [Line Items]
Amount of Issuance	$ 400
Date of Issuance	December 2006
Original attachment point (subordination)	5.50%
Current attachment point (subordination)	4.21%
Maturity	Dec. 20, 2016
Current rating of tranche	BBB-
Current rating of underlying reference obligations, high end of range	AA
Current rating of underlying reference obligations, low end of range	BB
Number of defaults in underlying collateral pool	3
Number of entities	123
Number of countries	20
Credit Linked Note Structure April 2007 [Member]
Credit Linked Notes Structures Summary Information [Line Items]
Amount of Issuance	$ 200
Date of Issuance	April 2007
Original attachment point (subordination)	2.05%
Current attachment point (subordination)	1.48%
Maturity	Mar. 20, 2017
Current rating of tranche	Ba2
Current rating of underlying reference obligations, high end of range	AAA
Current rating of underlying reference obligations, low end of range	CCC
Number of defaults in underlying collateral pool	2
Number of entities	99
Number of countries	21