CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash Flows from Operating Activities:
Net income	$ 377,702	$ 312,575
Change in operating assets and liabilities:
Accrued investment income	(34,676)	(34,705)
Premiums receivable and other reinsurance balances	(230,650)	(98,610)
Deferred policy acquisition costs	35,870	(5,435)
Reinsurance ceded receivable balances	(127,995)	(60,465)
Future policy benefits, other policy claims and benefits, and other reinsurance balances	745,799	380,297
Deferred income taxes	142,044	101,163
Other assets and other liabilities, net	(63,811)	(43,708)
Amortization of net investment premiums, discounts and other	(47,563)	(42,843)
Depreciation, Depletion and Amortization	13,869	12,888
Investment related (gains) losses, net	(116,818)	2,622
Other, net	(37,797)	70,667
Net cash provided by operating activities	655,974	594,446
Cash Flows from Investing Activities:
Sales of fixed maturity securities available-for-sale	4,288,713	2,271,414
Maturities of fixed maturity securities available-for-sale	313,530	273,552
Proceeds from Sale of Available-for-sale Securities, Equity	166,916	132,932
Payments to Acquire Available-for-sale Securities, Debt	5,311,818	4,416,290
Payments to Acquire Available-for-sale Securities, Equity	(32,299)	(408,684)
Payments to Acquire Mortgage Notes Receivable	(463,063)	(543,454)
Proceeds from Sale and Collection of Mortgage Notes Receivable	135,450	294,843
Proceeds from Collection of Policy Loans	26,658	25,065
Payments for (Proceeds from) Policy Loans	5,830	1,679
Increase (Decrease) in Funds Held under Reinsurance Agreements	6,910	27,868
Payments to Acquire Property, Plant, and Equipment	31,686	0
Change in short-term investments	22,671	350,062
Change in other invested assets	(55,379)	(8,100)
Net cash used in investing activities	(889,675)	(2,058,207)
Cash Flows from Financing Activities:
Dividends to stockholders	(52,815)	(47,746)
Proceeds from (Repayments of) Secured Debt	(23,761)	(35,369)
Proceeds from Issuance of Long-term Debt	0	799,984
Payments of Debt Issuance Costs	0	(9,026)
Repayments of Long-term Debt	(301,278)	(1,227)
Purchases of treasury stock	(10,578)	(120,806)
Exercise of stock options, net	2,527	5,219
Change in cash collateral for derivative positions and other arrangements	(7,046)	57,055
Deposits on universal life and other investment type policies and contracts	917,675	513,679
Withdrawals on universal life and other investment type policies and contracts	(402,528)	(208,743)
Net cash provided by financing activities	122,196	953,020
Effect of exchange rate changes on cash	34,137	19,795
Change in cash and cash equivalents	(77,368)	(490,946)
Cash and cash equivalents, beginning of period	1,200,718	1,525,275
Cash and cash equivalents, end of period	1,123,350	1,034,329
Supplemental disclosures of cash flow information:
Interest Paid, Net	90,425	68,445
Income Taxes Paid, Net	26,447	43,838
Transfer to Investments	$ 2,243,360	$ 1,730