CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash flows from operating activities:
Net income	$ 330,451	$ 208,420
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	31,395	33,191
Deferred tax expense	92,428	106,163
Net realized investment losses	2,226	177
Loss on debt extinguishment	0	65
Change in certain assets and liabilities:
Accrued investment income	(1,065)	43
Reinsurance recoverable on loss reserves	11,423	5,710
Reinsurance recoverable on paid losses	577	(1,187)
Premium receivable	(2,168)	1,048
Deferred insurance policy acquisition costs	34	(918)
Profit commission receivable	(11,202)	(4,603)
Loss reserves	(172,620)	(251,724)
Unearned premiums	13,225	22,273
Return premium accrual	(12,200)	(11,900)
Income taxes payable - current	(11,321)	32,991
Other, net	(8,590)	(14,193)
Net cash provided by operating activities	262,593	125,556
Cash flows from investing activities:
Purchases of investments	(516,712)	(545,319)
Proceeds from sales of investments	25,185	166,606
Proceeds from maturity of fixed income securities	423,933	390,344
Net increase in payable for securities	13,432	3,447
Additions to property and equipment	(8,256)	(9,659)
Net cash (used in) provided by investing activities	(62,418)	5,419
Cash flows from financing activities:
Proceeds from revolving credit facility	0	150,000
Repayment of revolving credit facility	0	(150,000)
Purchase or repayment of convertible senior notes	0	(145,620)
Payment of original issue discount - convertible senior notes	0	(4,504)
Repurchase of common stock	(100,059)	0
Payment of debt issuance costs	0	(1,630)
Payment of withholding taxes related to share-based compensation net share settlement	(8,073)	(6,723)
Net cash used in financing activities	(108,132)	(158,477)
Net increase (decrease) in cash and cash equivalents	92,043	(27,502)
Cash and cash equivalents at beginning of period	99,851	155,410
Cash and cash equivalents at end of period	$ 191,894	$ 127,908