CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash Flows from Operating Activities:
Net income	$ 312,575	$ 255,505
Change in operating assets and liabilities:
Accrued investment income	(34,705)	(26,656)
Premiums receivable and other reinsurance balances	(98,610)	(19,683)
Deferred policy acquisition costs	(5,435)	5,136
Reinsurance ceded receivable balances	(60,465)	(115,355)
Future policy benefits, other policy claims and benefits, and other reinsurance balances	380,297	353,946
Deferred income taxes	101,163	77,047
Other assets and other liabilities, net	(43,708)	42,363
Amortization of net investment premiums, discounts and other	(42,843)	(39,021)
Investment related (gains) losses, net	2,622	8,595
Other, net	83,555	63,815
Net cash provided by operating activities	594,446	605,692
Cash Flows from Investing Activities:
Sales of fixed maturity securities available-for-sale	2,271,414	2,742,814
Maturities of fixed maturity securities available-for-sale	273,552	232,712
Proceeds from Sale of Available-for-sale Securities, Equity	132,932	50,083
Payments to Acquire Mortgage Notes Receivable	(294,843)	(166,583)
Payments to Fund Policy Loans	(25,065)	(441)
Payments to Acquire Available-for-sale Securities, Debt	4,416,290	2,806,351
Payments to Acquire Available-for-sale Securities, Equity	408,684	68,116
Proceeds from Sale and Collection of Mortgage Notes Receivable	(543,454)	(531,317)
Payments for (Proceeds from) Policy Loans	1,679	686
Increase (Decrease) in Funds Held under Reinsurance Agreements	27,868	57,708
Payments to Acquire Businesses, Net of Cash Acquired	0	191,450
Payments to Acquire Property, Plant, and Equipment	0	(22,944)
Increase (Decrease) in Payables under Repurchase Agreements	0	(101,203)
Change in short-term investments	350,062	22,543
Change in other invested assets	(8,100)	91,562
Net cash used in investing activities	(2,058,207)	(473,037)
Cash Flows from Financing Activities:
Dividends to stockholders	(47,746)	(44,519)
Proceeds from (Repayments of) Secured Debt	(35,369)	(17,632)
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)	(1,170)
Repayments of Long-term Debt	(1,227)	(1,178)
Purchases of treasury stock	(120,806)	(262,515)
Exercise of stock options, net	5,219	12,641
Change in cash collateral for derivative positions and other arrangements	57,055	(31,244)
Deposits on universal life and other investment type policies and contracts	513,679	132,679
Withdrawals on universal life and other investment type policies and contracts	(208,743)	(363,600)
Net cash provided by (used in) financing activities	953,020	(416,478)
Effect of exchange rate changes on cash	19,795	(26,185)
Change in cash and cash equivalents	(490,946)	(310,008)
Cash and cash equivalents, beginning of period	1,525,275	1,645,669
Cash and cash equivalents, end of period	1,034,329	1,335,661
Supplemental disclosures of cash flow information:
Interest Paid, Net	68,445	74,637
Income Taxes Paid, Net	43,838	(19,307)
Transfer to Investments	1,730	118
Capital Expenditures Incurred but Not yet Paid	0	2,121
Noncash or Part Noncash Acquisition, Value of Assets Acquired	0	3,681,699
Noncash or Part Noncash Acquisition, Value of Liabilities Assumed	0	(3,490,249)
Payments to Acquire Businesses, Net of Cash Acquired	$ 0	$ 191,450