Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net Cash Provided by (Used in) Operating Activities	$ 206,412	$ 150,796
Cash flows from investing activities:
Proceeds from Sale and Maturity of Fixed-Maturity Investments Available-for-sale	649,687	306,575
Proceeds from Sale of Available-for-sale Securities, Equity	18,103	74,868
Proceeds from Sale of Trading Securities Held-for-investment	130,022	150,118
Proceeds from Redemption of Fixed-Maturity Investments Available-for-sale	260,848	137,909
Proceeds from Redemption of Trading Securities Held-for-investment	43,603	60,127
Purchases of Fixed-Maturity Investments Available-for-sale	(1,147,875)	(1,170,474)
Equity securities available for sale	(193,409)	0
Sales, Redemptions and (Purchases) of Short-term Investments	201,942	276,292
Sales, Redemptions and (Purchases) of Other assets and other invested assets, net	412	1,157
Purchases of property and equipment, net	(13,444)	(16,626)
Acquisitions, net of cash acquired	(86)	0
Net cash provided by (used in) investing activities	(50,197)	(180,054)
Cash flows from financing activities:
Dividends paid	(1,076)	(1,033)
Issuance of long-term debt, net	0	343,549
Purchases and redemptions of long-term debt	(141,686)	(208,251)
Proceeds from termination of capped calls	4,083	0
Issuance of common stock	3,123	65
Purchase of common shares	(6)	(100,188)
Excess tax benefits from share-based awards (Note 1)	0	63
Repayment of other borrowings	(140)	(206)
Net cash provided by (used in) financing activities	(135,702)	33,999
Effect of exchange rate changes on cash and restricted cash	77	(279)
Increase (decrease) in cash and restricted cash	20,590	4,462
Cash and restricted cash, beginning of period	61,814	59,898
Cash and restricted cash, end of period	$ 82,404	$ 64,360