Investments (Tables)

6 Months Ended

Jun. 30, 2015

Investments [Abstract]

Schedule of trading securities

Securities accounted for at fair value with changes in fair value recognized in the consolidated income statements by category are as follows:

	June 30, 2015				December 31, 2014
	Fair Value		Amortized Cost		Fair Value		Amortized Cost
U.S. government and government agencies	$	1,280,844	$	1,277,547	$	1,610,502	$	1,610,880
Non-U.S. government and government agencies	411,550		421,778		188,199		196,332
States, municipalities and political subdivisions	348,823		348,288		170,567		165,615
Corporate debt:
Financial institutions	1,055,836		1,053,576		1,024,667		1,018,777
Industrials	1,226,827		1,238,948		1,029,729		1,037,820
Utilities	121,571		122,793		110,997		111,599
Mortgage-backed	1,263,019		1,234,126		1,263,517		1,219,712
Asset-backed	723,073		727,919		670,832		674,505
Total fixed maturity investments	$	6,431,543	$	6,424,975	$	6,069,010	$	6,035,240

	June 30, 2015				December 31, 2014
	Fair Value		Original Cost		Fair Value		Original Cost
Equity securities	$	815,641	$	757,592	$	844,163	$	791,206
Other invested assets	769,173		685,897		812,543		725,069
	$	1,584,814	$	1,443,489	$	1,656,706	$	1,516,275

Schedule of other invested assets

Details regarding the carrying value, redemption characteristics and unfunded investment commitments of the other invested assets portfolio as of June 30, 2015 and December 31, 2014 were as follows:

Investment Type	Carrying Value as of June 30, 2015		Investments with Redemption Restrictions		Estimated Remaining Restriction Period	Investments without Redemption Restrictions		Redemption Frequency(1)	Redemption Notice Period(1)	Unfunded Commitments
Private equity	$	198,302	$	198,302	2 - 8 Years	$	—			$	180,988
Mezzanine debt	183,002		183,002		5 - 9 Years	—				255,333
Distressed	6,088		6,088		3 Years	—				5,561
Real estate	—		—		9 Years	—				150,000
Total private equity	387,392		387,392			—				591,882
Distressed	170,858		—			—		Based on net asset value	60 Days	—
Equity long/short	60,103		—			60,103		Quarterly	30 -60 Days	—
Relative value credit	120,939		—			120,939		Quarterly	60 Days	—
Total hedge funds	351,900		—			181,042				—
High yield loan fund	29,881		—			29,881		Monthly	30 days	—
Total other invested assets at fair value	769,173		387,392			210,923				591,882
Other private securities	127,617		—			127,617				—
Total other invested assets	$	896,790	$	387,392		$	338,540			$	591,882

Investment Type	Carrying Value as of December 31, 2014		Investments with Redemption Restrictions		Estimated Remaining Restriction Period	Investments without Redemption Restrictions		Redemption Frequency(1)	Redemption Notice Period(1)	Unfunded Commitments
Private equity	$	184,576	$	184,576	2 - 8 Years	$	—			$	223,802
Mezzanine debt	166,905		166,905		5 - 9 Years	—				204,232
Distressed	5,869		5,869		3 Years	—				5,180
Real estate	—		—		9 Years	—				50,000
Total private equity	357,350		357,350			—				483,214
Distressed	170,169		170,169		1 Year	—		Based on net asset value	60 Days	—
Equity long/short	84,198		—			84,198		Quarterly	30 -60 Days	—
Multi-strategy	51,507		—			51,507		Quarterly	45 -90 Days	—
Relative value credit	119,156		—			119,156		Quarterly	60 Days	—
Total hedge funds	425,030		170,169			254,861				—
High yield loan fund	30,163		—			30,163		Monthly	30 days	—
Total other invested assets at fair value	812,543		527,519			285,024				483,214
Other private securities	142,966		—			142,966				—
Total other invested assets	$	955,509	$	527,519		$	427,990			$	483,214

_______________________

(1) The redemption frequency and notice periods only apply to the investments without redemption restrictions. Some or all of these investments may be subject to a gate as described below.

Schedule of net investment income

	Three Months Ended   June 30,						Six Months Ended   June 30,
	2015			2014			2015			2014
Fixed maturity investments	$	41,205		$	35,936		$	77,463		$	72,235
Equity securities	4,862			5,912			8,425			9,165
Other invested assets: hedge funds and private equity	4,583			2,527			12,963			6,519
Other invested assets: other private securities	(3,789		)	(3,417		)	(2,923		)	3,999
Cash and cash equivalents	439			571			901			1,010
Expenses	(4,540		)	(4,736		)	(9,518		)	(8,516		)
Net investment income	$	42,760		$	36,793		$	87,311		$	84,412

Components of realized gains and losses

	Three Months Ended   June 30,						Six Months Ended   June 30,
	2015			2014			2015			2014
Gross realized gains on sale of invested assets	$	36,079		$	55,714		$	81,368		$	118,006
Gross realized losses on sale of invested assets	(10,059		)	(4,025		)	(23,063		)	(16,273		)
Net realized and unrealized gains (losses) on derivatives	13,920			(13,720		)	2,288			(26,640		)
Mark-to-market (losses) gains:
Fixed maturity investments, trading	(52,688		)	36,426			(27,171		)	58,882
Equity securities, trading	(329		)	21,316			5,091			(289		)
Other invested assets, trading	(7,105		)	(10,494		)	(13,670		)	5,736
Net realized investment (losses) gains	$	(20,182	)	$	85,217		$	24,843		$	139,422