Preneed Activities Schedule of Available-for-sale Securities (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Document Period End Date	Sep. 30, 2018
Amortized Cost Basis	$ 3,442,530	$ 3,260,648
Accumulated Gross Unrealized Gain, before Tax	372,154	367,569
Accumulated Gross Unrealized Loss, before Tax	(110,279)	(57,889)
Available-for-sale Securities, Fair Value	3,704,405	3,570,328
Reported at net asset value
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	1,226,471	1,122,537
Accumulated Gross Unrealized Gain, before Tax	111,408	64,692
Accumulated Gross Unrealized Loss, before Tax	(18,877)	(8,009)
Available-for-sale Securities, Fair Value	1,319,002	1,179,220
Estimate of Fair Value Measurement [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	4,669,001	4,383,185
Accumulated Gross Unrealized Gain, before Tax	483,562	432,261
Accumulated Gross Unrealized Loss, before Tax	(129,156)	(65,898)
Available-for-sale Securities, Fair Value	5,023,407	4,749,548
Fixed Income Commingled funds [Member] | Reported at net asset value
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	427,226	454,242
Accumulated Gross Unrealized Gain, before Tax	2,462	235
Accumulated Gross Unrealized Loss, before Tax	(17,359)	(5,860)
Available-for-sale Securities, Fair Value	412,329	448,617
Commingled funds - Equity [Member] | Reported at net asset value
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	206,040	214,000
Accumulated Gross Unrealized Gain, before Tax	40,558	12,826
Accumulated Gross Unrealized Loss, before Tax	(2)	0
Available-for-sale Securities, Fair Value	246,596	226,826
Private Equity Funds | Reported at net asset value
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	212,462	166,860
Accumulated Gross Unrealized Gain, before Tax	68,388	51,631
Accumulated Gross Unrealized Loss, before Tax	(1,516)	(2,149)
Available-for-sale Securities, Fair Value	279,334	216,342
Money Market Funds [Member] | Reported at net asset value
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	380,743	287,435
Accumulated Gross Unrealized Gain, before Tax	0	0
Accumulated Gross Unrealized Loss, before Tax	0	0
Available-for-sale Securities, Fair Value	380,743	287,435
Fair Value, Inputs, Level 2 | US Treasury Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	49,924	48,805
Accumulated Gross Unrealized Gain, before Tax	14	14
Accumulated Gross Unrealized Loss, before Tax	(621)	(117)
Available-for-sale Securities, Fair Value	49,317	48,702
Fair Value, Inputs, Level 2 | Foreign Government Debt Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	59,507	81,500
Accumulated Gross Unrealized Gain, before Tax	36	160
Accumulated Gross Unrealized Loss, before Tax	(1,738)	(1,089)
Available-for-sale Securities, Fair Value	57,805	80,571
Fair Value, Inputs, Level 2 | Corporate Debt Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	24,962	13,540
Accumulated Gross Unrealized Gain, before Tax	67	327
Accumulated Gross Unrealized Loss, before Tax	(336)	(170)
Available-for-sale Securities, Fair Value	24,693	13,697
Fair Value, Inputs, Level 2 | Residential Mortgage Backed Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	3,809	3,279
Accumulated Gross Unrealized Gain, before Tax	10	16
Accumulated Gross Unrealized Loss, before Tax	(91)	(14)
Available-for-sale Securities, Fair Value	3,728	3,281
Fair Value, Inputs, Level 2 | Asset-backed Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	142	320
Accumulated Gross Unrealized Gain, before Tax	2	15
Accumulated Gross Unrealized Loss, before Tax	(10)	(10)
Available-for-sale Securities, Fair Value	134	325
Fair Value, Inputs, Level 2 | Preferred Stock Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	10,080	7,834
Accumulated Gross Unrealized Gain, before Tax	891	385
Accumulated Gross Unrealized Loss, before Tax	(186)	(139)
Available-for-sale Securities, Fair Value	10,785	8,080
Fair Value, Inputs, Level 1 | US Common Stock Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	1,208,054	1,161,015
Accumulated Gross Unrealized Gain, before Tax	295,891	266,822
Accumulated Gross Unrealized Loss, before Tax	(42,913)	(24,739)
Available-for-sale Securities, Fair Value	1,461,032	1,403,098
Fair Value, Inputs, Level 1 | Canada Common Stock Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	36,162	30,762
Accumulated Gross Unrealized Gain, before Tax	11,804	12,545
Accumulated Gross Unrealized Loss, before Tax	(1,425)	(522)
Available-for-sale Securities, Fair Value	46,541	42,785
Fair Value, Inputs, Level 1 | Other International Common Stock Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	75,039	63,510
Accumulated Gross Unrealized Gain, before Tax	10,707	13,174
Accumulated Gross Unrealized Loss, before Tax	(4,613)	(2,834)
Available-for-sale Securities, Fair Value	81,133	73,850
Fair Value, Inputs, Level 1 | Equity Funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	728,307	613,934
Accumulated Gross Unrealized Gain, before Tax	45,012	59,100
Accumulated Gross Unrealized Loss, before Tax	(12,089)	(4,312)
Available-for-sale Securities, Fair Value	761,230	668,722
Fair Value, Inputs, Level 1 | Fixed Income Funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	1,231,818	1,230,196
Accumulated Gross Unrealized Gain, before Tax	3,492	11,897
Accumulated Gross Unrealized Loss, before Tax	(46,257)	(23,943)
Available-for-sale Securities, Fair Value	1,189,053	1,218,150
Fair Value, Inputs, Level 3 | Other Investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	14,726	5,953
Accumulated Gross Unrealized Gain, before Tax	4,228	3,114
Accumulated Gross Unrealized Loss, before Tax	0	0
Available-for-sale Securities, Fair Value	$ 18,954	$ 9,067