Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2017

Fair Value Disclosures [Abstract]

Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis

Below is a summary of the assets and liabilities that are measured at fair value on a recurring basis and also represents the carrying amount on the Company’s consolidated balance sheets:

At March 31, 2017	Total			Quoted Prices in Active Markets for Identical  Assets (Level 1)			Significant Other Observable Inputs (Level 2)			Significant Unobservable Inputs (Level 3)
Fixed maturity investments
U.S. treasuries	$	2,635,800		$	2,635,800		$	—		$	—
Agencies	86,373			—			86,373			—
Municipal	506,109			—			506,109			—
Non-U.S. government (Sovereign debt)	341,725			—			341,725			—
Non-U.S. government-backed corporate	118,092			—			118,092			—
Corporate	2,205,442			—			2,205,442			—
Agency mortgage-backed	505,829			—			505,829			—
Non-agency mortgage-backed	270,983			—			270,983			—
Commercial mortgage-backed	382,874			—			382,874			—
Asset-backed	206,624			—			206,624			—
Total fixed maturity investments	7,259,851			2,635,800			4,624,051			—
Short term investments	1,199,797			—			1,199,797			—
Equity investments trading	388,424			388,424			—			—
Other investments
Catastrophe bonds	298,564			—			298,564			—
Private equity partnerships (1)	192,975			—			—			—
Senior secured bank loan funds (1)	21,748			—			—			—
Hedge funds (1)	1,380			—			—			—
Total other investments	514,667			—			298,564			—
Other assets and (liabilities)
Assumed and ceded (re)insurance contracts (2)	(12,135		)	—			—			(12,135		)
Derivatives (3)	(1,752		)	(53		)	(1,699		)	—
Other	(1,708		)	—			(1,708		)	—
Total other assets and (liabilities)	(15,595		)	(53		)	(3,407		)	(12,135		)
	$	9,347,144		$	3,024,171		$	6,119,005		$	(12,135	)

(1) Certain investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the consolidated balance sheet.

(2) Included in assumed and ceded (re)insurance contracts at March 31, 2017 was $4.7 million and $16.8 million of other assets and other liabilities, respectively.

(3) See “Note 12. Derivative Instruments” for additional information related to the fair value by type of contract, of derivatives entered into by the Company.

At December 31, 2016	Total			Quoted Prices in Active Markets for Identical  Assets (Level 1)			Significant Other Observable Inputs (Level 2)			Significant Unobservable Inputs (Level 3)
Fixed maturity investments
U.S. treasuries	$	2,617,894		$	2,617,894		$	—		$	—
Agencies	90,972			—			90,972			—
Municipal	519,069			—			519,069			—
Non-U.S. government (Sovereign debt)	333,224			—			333,224			—
Non-U.S. government-backed corporate	133,300			—			133,300			—
Corporate	1,877,243			—			1,877,243			—
Agency mortgage-backed	462,493			—			462,493			—
Non-agency mortgage-backed	258,944			—			258,944			—
Commercial mortgage-backed	409,747			—			409,747			—
Asset-backed	188,358			—			188,358			—
Total fixed maturity investments	6,891,244			2,617,894			4,273,350			—
Short term investments	1,368,379			—			1,368,379			—
Equity investments trading	383,313			383,313			—			—
Other investments
Catastrophe bonds	335,209			—			335,209			—
Private equity partnerships (1)	191,061			—			—			—
Senior secured bank loan funds (1)	22,040			—			—			—
Hedge funds (1)	1,495			—			—			—
Total other investments	549,805			—			335,209			—
Other assets and (liabilities)
Assumed and ceded (re)insurance contracts (2)	(13,004		)	—			—			(13,004		)
Derivatives (3)	(8,922		)	(646		)	(8,276		)	—
Other	(13,105		)	—			(13,105		)	—
Total other assets and (liabilities)	(35,031		)	(646		)	(21,381		)	(13,004		)
	$	9,157,710		$	3,000,561		$	5,955,557		$	(13,004	)

(1) Certain investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the consolidated balance sheet.

(2) Included in assumed and ceded (re)insurance contracts at December 31, 2016 was $4.4 million and $17.4 million of other assets and other liabilities, respectively.

(3) See “Note 12. Derivative Instruments” for additional information related to the fair value by type of contract, of derivatives entered into by the Company.

Schedule Of Quantitative Information Used As Level 3 Inputs

Below is a summary of quantitative information regarding the significant observable and unobservable inputs (Level 3) used in determining the fair value of assets and liabilities measured at fair value on a recurring basis:

At March 31, 2017	Fair Value (Level 3)			Valuation Technique	Unobservable (U) and Observable (O) Inputs	Low		High		Weighted Average or Actual
Other assets and (liabilities)
Assumed and ceded (re)insurance contracts	$	(180	)	Internal valuation model	Bond price (U)	$	101.02	$	107.15	$	104.41
					Liquidity discount (U)	n/a		n/a		1.3		%
Assumed and ceded (re)insurance contracts	(11,955		)	Internal valuation model	Net undiscounted cash flows (U)	n/a		n/a		$	(12,620	)
					Expected loss ratio (U)	n/a		n/a		33.1		%
					Net acquisition expense ratio (O)	n/a		n/a		(20.5		)%
					Contract period (O)	2.0 years		4.7 years		4.5 years
					Discount rate (U)	n/a		n/a		1.9		%
Total other assets and (liabilities)	$	(12,135	)

Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Level 3 Inputs

Below is a reconciliation of the beginning and ending balances, for the periods shown, of assets and liabilities measured at fair value on a recurring basis using Level 3 inputs. Interest and dividend income are included in net investment income and are excluded from the reconciliation.

	Other assets and (liabilities)
Balance - January 1, 2017	$	(13,004	)
Total realized gains
Included in other income	1,071
Purchases	(202		)
Balance - March 31, 2017	$	(12,135	)

	Fixed maturity investments trading			Other assets  and (liabilities)			Total
Balance - January 1, 2016	$	7,618		$	(5,899	)	$	1,719
Total unrealized losses
Included in net investment income	(118		)	—			(118		)
Total realized gains
Included in other income	—			1,700			1,700
Purchases	—			(525		)	(525		)
Balance - March 31, 2016	$	7,500		$	(4,724	)	$	2,776
Change in unrealized gains for the period included in earnings for assets held at the end of the period included in net investment income	$	(118	)	$	—		$	(118	)

Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Level 3 Inputs

Below is a reconciliation of the beginning and ending balances, for the periods shown, of assets and liabilities measured at fair value on a recurring basis using Level 3 inputs. Interest and dividend income are included in net investment income and are excluded from the reconciliation.

	Other assets and (liabilities)
Balance - January 1, 2017	$	(13,004	)
Total realized gains
Included in other income	1,071
Purchases	(202		)
Balance - March 31, 2017	$	(12,135	)

	Fixed maturity investments trading			Other assets  and (liabilities)			Total
Balance - January 1, 2016	$	7,618		$	(5,899	)	$	1,719
Total unrealized losses
Included in net investment income	(118		)	—			(118		)
Total realized gains
Included in other income	—			1,700			1,700
Purchases	—			(525		)	(525		)
Balance - March 31, 2016	$	7,500		$	(4,724	)	$	2,776
Change in unrealized gains for the period included in earnings for assets held at the end of the period included in net investment income	$	(118	)	$	—		$	(118	)

Schedule Of The Balances The Company Has Elected To Account For At Fair Value

Below is a summary of the balances the Company has elected to account for at fair value:

	March 31, 2017		December 31, 2016
Other investments	$	514,667	$	549,805
Other assets	$	4,666	$	4,379
Other liabilities	$	16,801	$	17,383

Schedule Of Other Investments Measured Using Net Asset Valuations

The table below shows the Company’s portfolio of other investments measured using net asset valuations as a practical expedient:

At March 31, 2017	Fair Value		Unfunded Commitments		Redemption Frequency	Redemption Notice Period (Minimum Days)	Redemption Notice Period (Maximum Days)
Private equity partnerships	$	192,975	$	218,142	See below	See below	See below
Senior secured bank loan funds	21,748		25,775		See below	See below	See below
Hedge funds	1,380		—		See below	See below	See below
Total other investments measured using net asset valuations	$	216,103	$	243,917