Fair Value (Tables)

6 Months Ended

Jun. 30, 2017

Fair Value Disclosures [Abstract]

Fair value hierarchy

The following table presents the Company’s financial assets and liabilities measured at fair value by level at June 30, 2017:

				Estimated Fair Value Measurements Using:
	Estimated Fair Value			Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)			Significant Unobservable Inputs (Level 3)
Assets measured at fair value (1):
Available for sale securities:
Fixed maturities:
Corporate bonds	$	4,262,411		$	—	$	4,250,841		$	11,570
Mortgage backed securities	331,082			—		331,082			—
Municipal bonds	2,618,827			—		2,618,827			—
Commercial mortgage backed securities	521,272			—		521,272			—
U.S. government and government agencies	3,425,196			3,360,752		64,444			—
Non-U.S. government securities	1,375,796			—		1,375,796			—
Asset backed securities	1,739,695			—		1,739,695			—
Total	14,274,279			3,360,752		10,901,957			11,570
Equity securities	467,870			463,015		4,855			—
Short-term investments	914,356			906,191		8,165			—
Other investments	170,402			170,402		—			—
Other investments measured at net asset value (2)	78,259
Total other investments	248,661			170,402		—			—
Derivative instruments (4)	30,215			—		30,215			—
Fair value option:
Corporate bonds	749,399			—		749,399			—
Non-U.S. government bonds	75,084			—		75,084			—
Mortgage backed securities	19,812			—		19,812			—
Asset backed securities	16,291			—		16,291			—
U.S. government and government agencies	209,583			209,583		—			—
Short-term investments	527,384			524,167		3,217			—
Equity securities	76,915			57,523		19,392			—
Other investments	1,392,973			92,860		1,275,113			25,000
Other investments measured at net asset value (2)	750,792
Total	3,818,233			884,133		2,158,308			25,000
Total assets measured at fair value	$	19,753,614		$	5,784,493	$	13,103,500		$	36,570
Liabilities measured at fair value:
Contingent consideration liabilities	$	(57,246	)	$	—	$	—		$	(57,246	)
Securities sold but not yet purchased (3)	(69,273		)	—		(69,273		)	—
Derivative instruments (4)	(35,004		)	—		(35,004		)	—
Total liabilities measured at fair value	$	(161,523	)	$	—	$	(104,277	)	$	(57,246	)

(1) In securities lending transactions, the Company receives collateral in excess of the fair value of the securities pledged. For purposes of this table, the Company has excluded the collateral received under securities lending, at fair value and included the securities pledged under securities lending, at fair value. See Note 7, “Investment Information—Securities Lending Agreements.”

(2) In accordance with applicable accounting guidance, 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 sheets.

(3) Represents the Company’s obligations to deliver securities that it did not own at the time of sale. Such amounts are included in “other liabilities” on the Company’s consolidated balance sheets.

(4) See Note 9, “Derivative Instruments.”

The following table presents the Company’s financial assets and liabilities measured at fair value by level at December 31, 2016:

				Estimated Fair Value Measurements Using:
	Estimated Fair Value			Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)			Significant Unobservable Inputs (Level 3)
Assets measured at fair value (1):
Available for sale securities:
Fixed maturities:
Corporate bonds	$	4,392,373		$	—	$	4,374,029		$	18,344
Mortgage backed securities	490,093			—		490,093			—
Municipal bonds	3,713,434			—		3,713,434			—
Commercial mortgage backed securities	536,051			—		536,051			—
U.S. government and government agencies	2,804,540			2,691,575		112,965			—
Non-U.S. government securities	1,096,440			—		1,096,440			—
Asset backed securities	1,123,987			—		1,112,698			11,289
Total	14,156,918			2,691,575		11,435,710			29,633
Equity securities	532,680			529,695		2,985			—
Short-term investments	612,005			608,862		3,143			—
Other investments	112,313			112,313		—			—
Other investments measured at net asset value (2)	55,657
Total other investments	167,970			112,313		—			—
Derivative instruments (4)	28,410			—		28,410			—
Fair value option:
Corporate bonds	790,935			—		790,935			—
Non-U.S. government bonds	61,747			—		61,747			—
Mortgage backed securities	18,624			—		18,624			—
Asset backed securities	30,324			—		30,324			—
U.S. government and government agencies	197,486			197,486		—			—
Short-term investments	373,669			309,127		64,542			—
Equity securities	27,642			25,328		2,314			—
Other investments	1,226,242			80,706		1,120,536			25,000
Other investments measured at net asset value (2)	694,551
Total	3,421,220			612,647		2,089,022			25,000
Total assets measured at fair value	$	18,919,203		$	4,555,092	$	13,559,270		$	54,633
Liabilities measured at fair value:
Contingent consideration liabilities	$	(122,350	)	$	—	$	—		$	(122,350	)
Securities sold but not yet purchased (3)	(33,157		)	—		(33,157		)	—
Derivative instruments (4)	(26,049		)	—		(26,049		)	—
Total liabilities measured at fair value	$	(181,556	)	$	—	$	(59,206	)	$	(122,350	)

(1) In securities lending transactions, the Company receives collateral in excess of the fair value of the securities pledged. For purposes of this table, the Company has excluded the collateral received under securities lending, at fair value and included the securities pledged under securities lending, at fair value. See Note 7, “Investment Information—Securities Lending Agreements.”

(2) In accordance with applicable accounting guidance, 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 sheets.

(3) Represents the Company’s obligations to deliver securities that it did not own at the time of sale. Such amounts are included in “other liabilities” on the Company’s consolidated balance sheets.

(4) See Note 9, “Derivative Instruments.”

Rollforward of Level 3 investments

The following table presents a reconciliation of the beginning and ending balances for all financial assets and liabilities measured at fair value on a recurring basis using Level 3 inputs:

	Assets											Liabilities
s	Available For Sale						Fair Value Option
	Asset Backed Securities			Corporate Bonds			Other Investments		Total			Contingent Consideration Liabilities
Three Months Ended June 30, 2017
Balance at beginning of period	$	10,637		$	18,601		$	25,000	$	54,238		$	(125,544	)
Total gains or (losses) (realized/unrealized)
Included in earnings (1)	3,072			636			—		3,708			(3,441		)
Included in other comprehensive income	—			—			—		—			—
Purchases, issuances, sales and settlements
Purchases	—			4,935			—		4,935			—
Issuances	—			—			—		—			—
Sales	(13,640		)	(12,602		)	—		(26,242		)	—
Settlements	(69		)	—			—		(69		)	71,739
Transfers in and/or out of Level 3	—			—			—		—			—
Balance at end of period	$	—		$	11,570		$	25,000	$	36,570		$	(57,246	)
Three Months Ended June 30, 2016
Balance at beginning of period	$	57,500		$	15,166		$	—	$	72,666		$	(100,710	)
Total gains or (losses) (realized/unrealized)
Included in earnings (1)	(2,500		)	1,363			—		(1,137		)	(10,923		)
Included in other comprehensive income	—			—			—		—			(37		)
Purchases, issuances, sales and settlements
Purchases	—			776			—		776			—
Issuances	—			—			—		—			—
Sales	—			—			—		—			—
Settlements	(5,789		)	—			—		(5,789		)	—
Transfers in and/or out of Level 3	—			—			—		—			—
Balance at end of period	$	49,211		$	17,305		$	—	$	66,516		$	(111,670	)
Six Months Ended June 30, 2017
Balance at beginning of year	$	11,289		$	18,344		$	25,000	$	54,633		$	(122,350	)
Total gains or (losses) (realized/unrealized)
Included in earnings (1)	3,779			893			—		4,672			(7,087		)
Included in other comprehensive income	—			—			—		—			—
Purchases, issuances, sales and settlements
Purchases	—			4,935			—		4,935			—
Issuances	—			—			—		—			—
Sales	(13,640		)	(12,602		)	—		(26,242		)	—
Settlements	(1,428		)	—			—		(1,428		)	72,191
Transfers in and/or out of Level 3	—			—			—		—			—
Balance at end of period	$	—		$	11,570		$	25,000	$	36,570		$	(57,246	)
Six Months Ended June 30, 2016
Balance at beginning of year	$	57,500		$	16,368		$	—	$	73,868		$	(96,048	)
Total gains or (losses) (realized/unrealized)
Included in earnings (1)	(2,500		)	161			—		(2,339		)	(16,121		)
Included in other comprehensive income	—			—			—		—			(37		)
Purchases, issuances, sales and settlements
Purchases	—			776			—		776			—
Issuances	—			—			—		—			—
Sales	—			—			—		—			—
Settlements	(5,789		)	—			—		(5,789		)	536
Transfers in and/or out of Level 3	—			—			—		—			—
Balance at end of period	$	49,211		$	17,305		$	—	$	66,516		$	(111,670	)

(1) For the 2017 periods, gains or losses were included in net realized gains (losses). For the 2016 periods, losses on asset backed securities were included in net impairment losses recognized in earnings gains or losses while gains or losses on corporate bonds and contingent consideration liabilities were included in net realized gains (losses).