Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 22,726	$ 13,910
Other comprehensive income (loss), net of tax:
Unrealized gains (losses) on available for sale securities arising during the period	8,952	(11,026)
Change in minimum pension liability		80
Other comprehensive income (loss)	8,952	(10,946)
Comprehensive income	$ 31,678	$ 2,964

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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