Unaudited Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Investments:
Fixed maturities available for sale, at fair value (amortized cost: $14,293,121 and $13,869,460)	$ 14,128,989	$ 13,876,003
Short-term investments available for sale, at fair value (amortized cost: $1,096,532 and $1,468,955)	1,096,798	1,469,042
Collateral received under securities lending, at fair value (amortized cost: $236,948 and $476,605)	236,956	476,615
Equity securities, at fair value	534,482	495,804
Other investments available for sale, at fair value (cost: $0 and $198,163)	0	264,989
Investments accounted for using the fair value option	4,111,611	4,216,237
Investments accounted for using the equity method	1,428,582	1,041,322
Total investments	21,537,418	21,840,012
Cash	526,628	606,199
Accrued investment income	114,307	113,133
Securities pledged under securities lending, at fair value (amortized cost: $229,857 and $463,181)	230,064	464,917
Premiums receivable	1,351,310	1,135,249
Reinsurance recoverable on unpaid and paid losses and loss adjustment expenses	2,727,303	2,540,143
Contractholder receivables	2,044,322	1,978,414
Ceded unearned premiums	1,014,663	926,611
Deferred acquisition costs net	569,817	535,824
Receivable for securities sold	143,809	205,536
Goodwill and intangible assets	593,008	652,611
Other assets	1,000,471	1,053,009
Total assets	31,853,120	32,051,658
Liabilities
Reserve for losses and loss adjustment expenses	11,424,337	11,383,792
Unearned premiums	3,833,540	3,622,314
Reinsurance balances payable	411,082	323,496
Contractholder payables	2,044,322	1,978,414
Collateral held for insured obligations	257,396	240,183
Senior notes	1,733,211	1,732,884
Revolving credit agreement borrowings	572,289	816,132
Securities lending payable	236,948	476,605
Payable for securities purchased	356,583	449,186
Other liabilities	752,399	782,717
Total liabilities	21,622,107	21,805,723
Commitments and Contingencies
Redeemable noncontrolling interests	206,105	205,922
Shareholders' Equity
Non-cumulative preferred shares	780,000	872,555
Convertible non-voting common equivalent preferred shares	0	489,627
Common shares ($0.0011 par, shares issued: 569,458,341 and 549,872,226)	633	611
Additional paid-in capital	1,760,606	1,230,617
Retained earnings	9,083,202	8,562,889
Accumulated other comprehensive income (loss), net of deferred income tax	(194,157)	118,044
Common shares held in treasury, at cost (shares: 164,021,704 and 156,938,409)	(2,266,529)	(2,077,741)
Total shareholders' equity available to Arch	9,163,755	9,196,602
Non-redeemable noncontrolling interests	861,153	843,411
Total shareholders' equity	10,024,908	10,040,013
Total liabilities, noncontrolling interests and shareholders' equity	$ 31,853,120	$ 32,051,658