Unaudited Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Comprehensive Income
Net income	$ 256,347	$ 199,099	$ 422,731	$ 473,134
Unrealized appreciation (decline) in value of available-for-sale investments:
Unrealized holding gains (losses) arising during period	(85,271)	92,969	(251,948)	193,761
Reclassification of net realized (gains) losses, net of income taxes, included in net income	36,643	(17,224)	99,104	(22,268)
Foreign currency translation adjustments	(12,595)	18,297	(11,313)	21,421
Comprehensive income	195,124	293,141	258,574	666,048
Net (income) loss attributable to noncontrolling interests	(12,701)	(13,932)	(28,662)	(34,840)
Other comprehensive (income) loss attributable to noncontrolling interests	1,077	76	1,750	68
Comprehensive income available to Arch	$ 183,500	$ 279,285	$ 231,662	$ 631,276

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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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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