Income Taxes (Asset/Liability) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Deferred tax assets:
Federal net operating loss capital loss and credit carryforwards	$ 41,582	$ 45,259
Deferred revenue	115,620	114,770
Bad debt reserves	5,161	7,506
Employee benefits	48,449	47,071
Accrued expenses and loss reserves	29,755	30,321
Other	324	9,481
Less: valuation allowance	(24,173)	(30,955)
Total deferred tax assets	216,718	223,453
Deferred tax liabilities:
Depreciable and amortizable assets	187,881	170,089
Investment in affiliates	16,985	20,612
Total deferred tax liabilities	204,866	190,701
Net deferred tax asset/(liability)	$ 11,852	$ 32,752