5. Additional Insurance Benefits (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2012	Dec. 31, 2011
Additional Insurance Benefits	$ 1,344,232	$ 1,359,710
GMWB
Additional Insurance Benefits	530,709	529,027
Average Attained Age Of Annuitant	63 years	62 years
GMIB
Additional Insurance Benefits	411,428	428,058
Average Attained Age Of Annuitant	63 years	63 years
GMAB
Additional Insurance Benefits	378,344	374,423
Average Attained Age Of Annuitant	57 years	57 years
GPAF
Additional Insurance Benefits	14,188	18,446
Average Attained Age Of Annuitant	78 years	77 years
COMBO
Additional Insurance Benefits	$ 9,563	$ 9,756
Average Attained Age Of Annuitant	61 years	60 years