CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash Flows from Operating Activities:
Net income	$ 511,294	$ 339,039
Change in operating assets and liabilities:
Accrued investment income	(58,863)	(47,088)
Premiums receivable and other reinsurance balances	(3,619)	(100,804)
Deferred policy acquisition costs	(15,059)	(42,855)
Reinsurance ceded receivable balances	(77,741)	(42,620)
Future policy benefits, other policy claims and benefits, and other reinsurance balances	479,606	594,389
Deferred income taxes	165,988	128,557
Other assets and other liabilities, net	29,343	(14,670)
Amortization of net investment premiums, discounts and other	(55,967)	(61,714)
Investment related (gains) losses, net	(84,002)	119,941
Excess Tax Benefit from Share-based Compensation, Operating Activities	0	(2,884)
Other, net	128,892	9,175
Net cash provided by operating activities	1,019,872	878,466
Cash Flows from Investing Activities:
Sales of fixed maturity securities available-for-sale	3,649,187	3,904,948
Maturities of fixed maturity securities available-for-sale	349,836	342,126
Proceeds from Sale of Available-for-sale Securities, Equity	331,978	63,797
Payments to Acquire Mortgage Notes Receivable	(377,671)	(223,807)
Payments to Fund Policy Loans	(59,518)	(531)
Payments to Acquire Available-for-sale Securities, Debt	5,938,302	3,746,290
Payments to Acquire Available-for-sale Securities, Equity	523,499	75,396
Proceeds from Sale and Collection of Mortgage Notes Receivable	(857,445)	(686,878)
Payments for (Proceeds from) Policy Loans	5,685	6,628
Increase (Decrease) in Funds Held under Reinsurance Agreements	31,222	63,390
Payments to Acquire Businesses, Net of Cash Acquired	0	195,151
Payments to Acquire Property, Plant, and Equipment	0	(24,240)
Increase (Decrease) in Payables under Repurchase Agreements	0	(101,203)
Change in short-term investments	418,625	35,014
Change in other invested assets	(78,068)	144,011
Net cash used in investing activities	(2,247,406)	(184,942)
Cash Flows from Financing Activities:
Dividends to stockholders	(74,034)	(69,111)
Proceeds from (Repayments of) Secured Debt	(60,971)	(19,732)
Proceeds from Issuance of Secured Debt	0	160,060
Proceeds from Issuance of Long-term Debt	799,984	0
Payments of Debt Issuance Costs	(9,026)	(1,074)
Repayments of Long-term Debt	(1,850)	(1,776)
Purchases of treasury stock	(121,896)	(333,432)
Excess Tax Benefit from Share-based Compensation, Financing Activities	0	2,884
Exercise of stock options, net	11,752	12,551
Change in cash collateral for derivative positions and other arrangements	24,749	60,202
Deposits on universal life and other investment type policies and contracts	874,708	204,456
Withdrawals on universal life and other investment type policies and contracts	(386,900)	(556,821)
Net cash provided by (used in) financing activities	1,056,516	(541,793)
Effect of exchange rate changes on cash	25,436	(49,708)
Change in cash and cash equivalents	(145,582)	102,023
Cash and cash equivalents, beginning of period	1,525,275	1,645,669
Cash and cash equivalents, end of period	1,379,693	1,747,692
Supplemental disclosures of cash flow information:
Interest Paid, Net	114,043	103,481
Income Taxes Paid, Net	47,312	13,494
Transfer to Investments	3,621	342,082
Capital Expenditures Incurred but Not yet Paid	0	804
Noncash or Part Noncash Acquisition, Value of Assets Acquired	0	3,685,708
Noncash or Part Noncash Acquisition, Value of Liabilities Assumed	0	(3,490,557)
Payments to Acquire Businesses, Net of Cash Acquired	$ 0	$ 195,151