CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Comprehensive income
Net income	$ 20,155	$ 15,318
Other comprehensive income, net of tax:
Change in net unrealized investment gains (losses) on securities	(107,096)	22,533
Change in net funded status of benefit plans	0	0
Cumulative effect of change in accounting principle	(15,041)	0
Other comprehensive income (loss)	(122,137)	22,533
Total	$ (101,982)	$ 37,851

Other Comprehensive Income (Loss), Change In Accounting Principle Adjustment, Net Of Tax

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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