INVESTMENT OPERATIONS (Details 2) (USD $)	Jun. 30, 2011
Investment operations
Amortized Cost	$ 22,636,404,000
Gross Unrealized Gains	1,274,713,000
Gross Unrealized Losses	(293,137,000)
Fair Value	23,617,980,000
Fixed maturities
Investment operations
Amortized Cost	22,269,375,000
Gross Unrealized Gains	1,265,682,000
Gross Unrealized Losses	(288,085,000)
Fair Value	23,246,972,000
Trading securities	2,900,000,000
Amortized Cost
Due in one year or less	625,459,000
Due after one year through five years	3,715,102,000
Due after five years through ten years	6,318,142,000
Due after ten years	11,610,672,000
Total	22,269,375,000
Fair Value
Due in one year or less	640,235,000
Due after one year through five years	3,875,630,000
Due after five years through ten years	6,669,230,000
Due after ten years	12,061,877,000
Total	23,246,972,000
Residential mortgage-backed securities
Investment operations
Amortized Cost	2,543,004,000
Gross Unrealized Gains	56,189,000
Gross Unrealized Losses	(109,030,000)
Fair Value	2,490,163,000
Commercial mortgage-backed securities
Investment operations
Amortized Cost	283,569,000
Gross Unrealized Gains	5,980,000
Gross Unrealized Losses	(2,045,000)
Fair Value	287,504,000
Other asset-backed securities
Investment operations
Amortized Cost	875,894,000
Gross Unrealized Gains	1,276,000
Gross Unrealized Losses	(32,907,000)
Fair Value	844,263,000
U.S. government-related securities
Investment operations
Amortized Cost	1,097,064,000
Gross Unrealized Gains	36,511,000
Gross Unrealized Losses	(2,262,000)
Fair Value	1,131,313,000
Other government-related securities
Investment operations
Amortized Cost	135,993,000
Gross Unrealized Gains	7,126,000
Fair Value	143,119,000
States, municipals, and political subdivisions
Investment operations
Amortized Cost	1,140,928,000
Gross Unrealized Gains	41,746,000
Gross Unrealized Losses	(7,852,000)
Fair Value	1,174,822,000
Corporate bonds
Investment operations
Amortized Cost	16,192,923,000
Gross Unrealized Gains	1,116,854,000
Gross Unrealized Losses	(133,989,000)
Fair Value	17,175,788,000
Equity securities
Investment operations
Amortized Cost	334,505,000
Gross Unrealized Gains	9,031,000
Gross Unrealized Losses	(5,052,000)
Fair Value	338,484,000
Trading securities	11,300,000
Short-term investments
Investment operations
Amortized Cost	32,524,000
Fair Value	32,524,000
Trading securities	$ 102,200,000