Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Comprehensive Income
Net income	$ 1,693,300	$ 727,821	$ 629,709
Unrealized appreciation (decline) in value of available-for-sale investments:
Unrealized holding gains (losses) arising during year	500,771	(270,057)	252,904
Reclassification of net realized gains, included in net income	(118,941)	144,573	(67,863)
Foreign currency translation adjustments	18,110	(24,830)	47,014
Comprehensive income	2,093,240	577,507	861,764
Net (income) loss attributable to noncontrolling interests	(56,981)	30,150	(10,431)
Other comprehensive (income) loss attributable to noncontrolling interests	(9,130)	3,346	530
Comprehensive income available to Arch	$ 2,027,129	$ 611,003	$ 851,863

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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