RESERVE FOR LOSSES AND LOSS EXPENSES (DETAILS 5) $ in Thousands	Dec. 31, 2016 USD ($) claim	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Dec. 31, 2009 USD ($)	Dec. 31, 2008 USD ($)	Dec. 31, 2007 USD ($)
Insurance [Member] | Property and Other Reserve Class [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 3,033,236
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2016 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	519,834
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 189,742
Cumulative Number of Reported Claims | claim	51,460
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2015 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 375,867	$ 378,216
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 38,959
Cumulative Number of Reported Claims | claim	43,312
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2014 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 442,392	467,335	$ 471,402
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 19,696
Cumulative Number of Reported Claims | claim	60,120
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2013 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 381,573	387,086	414,793	$ 421,113
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 10,120
Cumulative Number of Reported Claims | claim	51,231
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2012 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 422,394	426,457	446,790	470,059	$ 463,117
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 9,381
Cumulative Number of Reported Claims | claim	27,679
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2011 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 315,517	316,756	317,110	340,974	364,736	$ 386,326
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 2,583
Cumulative Number of Reported Claims | claim	3,736
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2010 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 115,888	116,193	117,130	122,700	147,867	155,368	$ 182,337
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 469
Cumulative Number of Reported Claims | claim	2,309
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2009 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 80,880	81,204	80,983	83,139	85,202	92,505	101,823	$ 120,169
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 815
Cumulative Number of Reported Claims | claim	1,483
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2008 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 231,713	232,738	234,488	238,882	240,324	255,880	265,330	273,666	$ 318,702
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 2,017
Cumulative Number of Reported Claims | claim	1,573
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2007 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 147,178	147,552	147,875	148,350	149,580	149,236	151,107	160,343	162,796	$ 209,411
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 449
Cumulative Number of Reported Claims | claim	834
Insurance [Member] | Marine Reserve Class [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 781,666
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2016 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	86,115
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 41,293
Cumulative Number of Reported Claims | claim	804
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2015 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 138,915	158,240
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 23,853
Cumulative Number of Reported Claims | claim	850
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2014 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 47,870	44,221	59,880
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 8,864
Cumulative Number of Reported Claims | claim	794
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2013 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 95,954	94,917	99,885	79,011
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 9,907
Cumulative Number of Reported Claims | claim	727
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2012 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 71,370	70,404	68,315	82,344	89,663
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 9,821
Cumulative Number of Reported Claims | claim	697
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2011 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 65,572	65,363	65,383	72,137	78,293	90,608
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 2,449
Cumulative Number of Reported Claims | claim	602
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2010 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 45,934	47,397	50,248	52,161	65,198	69,312	67,916
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ (1,368)
Cumulative Number of Reported Claims | claim	472
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2009 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 53,652	54,774	56,208	58,383	65,787	71,049	75,532	82,075
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 531
Cumulative Number of Reported Claims | claim	475
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2008 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 84,221	84,483	84,848	88,612	95,006	102,201	103,287	108,208	107,697
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 324
Cumulative Number of Reported Claims | claim	516
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2007 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 92,063	92,077	92,405	94,612	96,304	97,949	100,962	106,228	95,994	96,533
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 257
Cumulative Number of Reported Claims | claim	684
Insurance [Member] | Aviation Reserve Class [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 153,462
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2016 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	29,135
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 9,919
Cumulative Number of Reported Claims | claim	1,143
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2015 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 28,453	29,748
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 4,999
Cumulative Number of Reported Claims | claim	1,751
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2014 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 24,322	23,016	20,429
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 2,969
Cumulative Number of Reported Claims | claim	1,255
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2013 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 15,223	15,179	16,313	15,647
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 1,010
Cumulative Number of Reported Claims | claim	1,005
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2012 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 7,728	8,678	10,764	10,642	12,772
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 499
Cumulative Number of Reported Claims | claim	866
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2011 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 7,257	8,404	9,536	12,763	15,377	17,721
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 434
Cumulative Number of Reported Claims | claim	730
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2010 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 8,418	8,370	8,444	9,419	11,095	11,383	12,629
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 253
Cumulative Number of Reported Claims | claim	516
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2009 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 14,519	15,351	16,535	16,835	18,007	18,680	14,490	17,408
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 176
Cumulative Number of Reported Claims | claim	317
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2008 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 5,985	5,840	5,925	7,095	8,243	8,341	8,504	12,009	14,480
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 91
Cumulative Number of Reported Claims | claim	187
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2007 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 12,422	12,853	12,958	14,427	16,352	16,756	17,043	22,682	25,466	29,801
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 53
Cumulative Number of Reported Claims | claim	270
Insurance [Member] | Credit and Political Risk Reserve Class [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 665,275
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2016 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	43,756
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 19,043
Cumulative Number of Reported Claims | claim	1
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2015 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 30,368	30,329
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 7,059
Cumulative Number of Reported Claims | claim	3
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2014 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 67,109	70,712	38,825
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 9,247
Cumulative Number of Reported Claims | claim	5
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2013 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 9,880	9,759	25,684	26,439
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 1,600
Cumulative Number of Reported Claims | claim	1
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2012 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 10,319	12,447	12,435	15,672	32,602
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 10,282
Cumulative Number of Reported Claims | claim	4
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2011 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 45,036	48,333	48,361	47,706	48,665	58,154
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 17,400
Cumulative Number of Reported Claims | claim	4
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2010 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 72,099	65,009	64,975	65,595	63,259	63,179	62,415
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 6,900
Cumulative Number of Reported Claims | claim	6
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2009 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 339,557	335,278	335,258	335,398	335,525	326,017	305,277	248,082
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 1,740
Cumulative Number of Reported Claims | claim	24
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2008 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 44,410	45,200	45,600	45,551	45,551	45,554	48,715	63,552	52,993
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 0
Cumulative Number of Reported Claims | claim	9
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2007 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 2,741	3,667	3,642	3,609	898	898	5,253	16,695	44,972	50,812
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 200
Cumulative Number of Reported Claims | claim	2
Insurance [Member] | Professional Lines Reserve Class [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 3,307,104
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2016 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	348,076
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 312,698
Cumulative Number of Reported Claims | claim	8,935
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2015 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 401,660	401,941
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 277,836
Cumulative Number of Reported Claims | claim	10,178
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2014 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 451,917	443,665	435,447
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 244,910
Cumulative Number of Reported Claims | claim	10,017
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2013 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 398,776	430,517	425,400	410,537
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 161,370
Cumulative Number of Reported Claims | claim	9,835
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2012 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 397,517	408,870	401,976	399,610	353,693
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 108,180
Cumulative Number of Reported Claims | claim	8,805
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2011 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 368,830	355,008	348,860	359,448	342,063	341,302
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 69,175
Cumulative Number of Reported Claims | claim	7,633
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2010 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 195,869	173,104	195,831	218,436	255,337	257,527	251,985
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 44,799
Cumulative Number of Reported Claims | claim	5,975
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2009 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 223,700	247,495	245,939	263,157	256,731	258,134	257,354	251,995
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 14,856
Cumulative Number of Reported Claims | claim	6,148
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2008 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 324,197	326,623	328,628	309,268	295,953	299,422	280,329	279,486	240,809
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 23,024
Cumulative Number of Reported Claims | claim	4,582
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2007 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 196,562	197,765	202,636	201,294	217,901	221,708	248,741	249,780	247,155	221,212
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 4,683
Cumulative Number of Reported Claims | claim	3,596
Insurance [Member] | Liability Reserve Class [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 1,025,716
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2016 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	123,233
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 107,850
Cumulative Number of Reported Claims | claim	3,099
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2015 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 125,844	127,318
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 83,145
Cumulative Number of Reported Claims | claim	2,970
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2014 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 128,465	122,583	106,121
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 55,811
Cumulative Number of Reported Claims | claim	2,240
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2013 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 87,491	94,247	94,171	92,146
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 36,011
Cumulative Number of Reported Claims | claim	1,494
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2012 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 68,179	70,769	73,280	70,608	70,836
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 23,448
Cumulative Number of Reported Claims | claim	1,215
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2011 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 83,730	85,243	87,059	83,118	75,329	72,586
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 20,189
Cumulative Number of Reported Claims | claim	1,776
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2010 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 105,123	98,064	99,574	98,115	98,637	94,222	79,406
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 15,988
Cumulative Number of Reported Claims | claim	2,196
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2009 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 98,384	101,179	83,281	76,431	67,869	67,410	64,017	61,469
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 11,813
Cumulative Number of Reported Claims | claim	2,735
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2008 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 108,189	102,444	101,589	81,949	82,225	81,785	80,947	79,836	82,969
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 20,340
Cumulative Number of Reported Claims | claim	3,697
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2007 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 97,078	97,526	101,299	102,010	99,483	98,851	98,625	95,435	88,102	100,380
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 12,107
Cumulative Number of Reported Claims | claim	3,766
Reinsurance [Member] | Property and Other Reserve Class [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	$ 4,518,583
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2016 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	440,384
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	224,911
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2015 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	359,185	380,660
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	69,223
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2014 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	442,330	455,607	437,470
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	53,805
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2013 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	392,459	411,440	441,492	466,295
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	10,724
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2012 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	393,775	409,836	440,303	450,563	484,438
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	10,707
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2011 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	1,006,528	1,032,549	1,049,625	1,090,593	1,092,015	1,083,060
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	10,715
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2010 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	555,647	563,532	569,697	567,341	553,798	584,912	599,084
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	7,034
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2009 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	195,545	193,703	199,777	220,889	227,777	241,346	279,833	337,333
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	705
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2008 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	512,261	513,948	520,174	536,555	547,586	562,028	584,076	569,031	671,079
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	(296)
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2007 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	220,469	220,937	224,023	231,597	238,779	249,436	265,204	279,571	321,110	394,054
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	379
Reinsurance [Member] | Credit and Surety Reserve Class [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	1,108,807
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2016 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	138,876
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	72,455
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2015 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	161,178	156,959
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	46,635
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2014 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	139,026	131,887	132,483
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	34,983
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2013 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	136,024	139,761	148,760	161,647
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	23,760
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2012 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	134,620	142,639	145,147	142,870	155,730
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	19,094
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2011 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	96,269	104,414	106,196	99,640	101,752	117,902
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	9,658
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2010 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	71,016	72,316	79,568	83,888	86,340	92,842	112,888
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	6,397
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2009 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	90,893	91,346	94,541	99,872	100,177	100,943	117,004	137,963
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	2,968
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2008 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	87,130	87,638	88,619	92,118	93,339	92,151	92,784	102,595	79,689
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	1,456
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2007 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	53,775	52,838	53,938	45,853	39,584	39,015	40,395	44,789	53,197	48,646
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	915
Reinsurance [Member] | Professional Lines Reserve Class [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	1,925,942
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2016 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	194,558
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	183,486
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2015 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	211,181	211,420
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	163,900
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2014 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	218,610	218,662	218,734
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	120,754
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2013 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	212,763	214,659	213,810	208,804
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	114,919
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2012 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	221,722	223,023	221,036	215,586	209,109
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	94,535
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2011 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	207,237	208,126	210,770	201,989	200,776	200,400
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	75,492
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2010 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	188,729	196,067	213,316	213,560	210,413	209,034	208,718
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	42,307
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2009 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	189,290	192,974	207,939	208,234	217,656	215,065	210,413	210,606
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	21,035
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2008 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	170,596	170,509	172,414	171,409	175,203	177,038	181,097	181,729	174,881
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	14,293
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2007 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	111,256	114,714	118,321	137,392	151,628	176,792	196,696	204,594	204,971	195,045
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	8,173
Reinsurance [Member] | Motor Reserve Class [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	1,291,908
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2016 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	238,258
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	100,635
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2015 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	207,409	215,342
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	49,375
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2014 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	168,846	173,568	175,848
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	33,650
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2013 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	130,299	139,138	150,277	155,880
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	30,902
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2012 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	137,841	142,454	149,420	159,822	170,379
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	37,418
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2011 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	148,843	156,912	160,516	155,096	151,432	149,535
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	44,483
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2010 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	77,560	86,409	91,248	96,811	97,823	97,598	92,168
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	27,778
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2009 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	73,670	78,929	87,017	85,870	83,944	82,170	75,034	77,092
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	17,780
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2008 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	54,678	58,250	63,627	67,783	68,486	70,961	68,617	69,234	64,513
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	18,178
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2007 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	54,504	55,279	58,086	59,548	60,568	63,813	62,768	62,829	66,567	65,601
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	14,117
Reinsurance [Member] | Liability Reserve Class [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	1,750,303
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2016 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	238,524
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	199,828
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2015 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	213,776	213,387
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	157,257
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2014 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	203,252	201,551	198,634
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	124,579
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2013 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	182,813	180,802	174,885	171,121
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	83,598
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2012 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	172,176	171,033	166,492	162,127	165,409
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	55,572
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2011 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	193,749	196,805	190,043	172,708	170,606	170,182
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	45,166
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2010 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	180,860	189,531	199,656	181,663	180,949	168,929	169,442
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	53,863
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2009 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	177,852	191,701	203,553	184,378	176,853	179,239	171,868	169,886
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	34,578
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2008 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	94,589	105,286	110,545	132,317	137,793	139,592	138,926	137,932	137,646
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	20,513
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2007 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	92,712	$ 97,515	$ 114,939	$ 144,241	$ 157,822	$ 157,886	$ 157,966	$ 158,773	$ 157,947	$ 160,455
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims	$ 11,940