CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Income and Comprehensive Income
Net Income		$ 96,226	$ 88,987	$ 189,171	$ 173,986
Other comprehensive income (loss) before tax:
Foreing currency translation adjustment	[1]	(1,588)	(1,435)	(1,449)	(2,140)
Amortization of net losses		5,606	5,487	11,213	10,973
Amortization of prior service credit		(950)	(950)	(1,900)	(1,900)
Unrealized holding (losses) gains on investments arising during the period		8,804	38,092	5,897	114,328
Other-than-temporary impairment included in net income		8,299	209	8,299	209
Reclassification adjustment for (gains) losses included in net income (loss)		(19)	0	(181)	0
Unrealized net (losses) gains on cash flow hedges		(377)	(1,539)	(1,014)	(3,539)
Reclassification adjustment for net (gains) losses included in net income		1,035	1,271	1,890	2,816
Other comprehensive income (loss) before tax		20,810	41,135	22,755	120,747
Income tax benefit (expense)		(3,841)	(4,997)	(5,412)	(9,473)
Total other comprehensive loss, net of tax		16,969	36,138	17,343	111,274
Comprehensive income (loss), net of tax		$ 113,195	$ 125,125	$ 206,514	$ 285,260

[1] All amounts presented are net of tax.