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	$ 115,176	$ 104,502
Adjustments to reconcile net income to cash provided by (used in) operating activities:
Change in future policy benefits and other policy liabilities	139,105	116,415
Deferral of policy acquisition costs	(208,391)	(183,145)
Amortization of deferred policy acquisition costs	99,710	81,849
Change in income taxes	5,782	36,306
Excess tax benefits on share-based compensation	4,238	1,448
Realized investment (gains) losses, including other-than-temporary impairments	(238)	(2,657)
Accretion and amortization of investments	(684)	(723)
Depreciation and amortization	6,994	7,108
Change in due from reinsurers	11,394	(17,062)
Change in agent balances, due premiums and other receivables	(13,475)	(24,445)
Trading securities sold, matured, or called (acquired), net	(8,173)	(2,658)
Share-based compensation	11,667	10,031
Change in other operating assets and liabilities, net	(43,235)	(21,620)
Net cash provided by (used in) operating activities	119,870	105,349
Available-for-sale investments sold, matured or called:
Fixed-maturity securities — sold	43,232	69,925
Fixed-maturity securities — matured or called	98,904	137,044
Equity securities	562	3,297
Available-for-sale investments acquired:
Fixed-maturity securities	(214,974)	(133,604)
Equity securities	(212)	(986)
Purchases of property and equipment and other investing activities, net	(6,194)	(10,679)
Cash collateral received (returned) on loaned securities, net	42,229	20,419
Sales (purchases) of short-term investments using securities lending collateral, net	(42,229)	(20,419)
Net cash provided by (used in) investing activities	(78,682)	64,997
Cash flows from financing activities:
Dividends paid	(17,680)	(16,446)
Common stock repurchased	(75,042)	(90,558)
Tax withholdings on share-based compensation	(6,497)	(3,757)
Net cash provided by (used in) financing activities	(99,219)	(110,761)
Effect of foreign exchange rate changes on cash	554	1,212
Change in cash and cash equivalents	(57,477)	60,797
Cash and cash equivalents, beginning of period	211,976	152,294
Cash and cash equivalents, end of period	$ 154,499	$ 213,091