Schedule II - Valuation and Qualifying Accounts and Reserves - Valuation Allowances and Reserves (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for Insurance and Claims Accruals [Member]
Balance at Beginning of Year		$ 28,103	$ 26,177	$ 19,440
Charged to Costs and Expenses		56,075	56,122	53,609
Deductions	[1]	(52,449)	(54,196)	(46,872)
Balance at End of Year		31,729	28,103	26,177
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
Balance at Beginning of Year		348	300	275
Charged to Costs and Expenses		65	163	33
Deductions	[2]	(31)	(115)	(8)
Balance at End of Year		$ 382	$ 348	$ 300

[1] Claims payments

[2] Write-off of bad debts, net of recoveries