Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance, beginning of period at Dec. 31, 2016		$ 457	$ 52,468	$ 1,138,851	$ 29,598
Repurchases of common stock		(11)	(69,556)	(11,972)
Share-based compensation			17,092
Net issuance of common stock		4	(4)
Net income	$ 115,176			115,176
Dividends				(17,680)
Change in foreign currency translation adjustment, net of income tax expense (benefit)					7,792
Change in net unrealized investment gains (losses) not-other- than temporarily impaired					7,031
Change in net unrealized investment gains (losses) other-than-temporarily impaired					7
Balance, end of period at Jun. 30, 2017	1,269,253	450		1,224,375	44,428
Balance, beginning of period at Dec. 31, 2017	1,419,101	443		1,375,090	43,568
Cumulative effect from the adoption of new accounting standards, net				24,610	73
Repurchases of common stock		(14)	(18,353)	(120,646)
Share-based compensation			18,356
Net issuance of common stock		3	$ (3)
Net income	152,414			152,414
Dividends				(22,364)
Change in foreign currency translation adjustment, net of income tax expense (benefit)					(14,304)
Change in net unrealized investment gains (losses) not-other- than temporarily impaired					(38,266)
Change in net unrealized investment gains (losses) other-than-temporarily impaired					(23)
Balance, end of period at Jun. 30, 2018	$ 1,400,584	$ 432		$ 1,409,104	$ (8,952)

Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation.

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