Investments in Equity Securities Available for Sale (Investments in Equity Securities Available for Sale) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Cost	$ 203,627	$ 308,175
Gross Unrealized, Gains	86,030	70,205
Gross Unrealized, Losses	(6,319)	(2,358)
Carrying value and fair value of equity securities	283,338	376,022
Common stocks
Schedule of Available-for-sale Securities [Line Items]
Cost	118,536	222,671
Gross Unrealized, Gains	42,239	60,102
Gross Unrealized, Losses	0	(707)
Carrying value and fair value of equity securities	160,775	282,066
Preferred stocks
Schedule of Available-for-sale Securities [Line Items]
Cost	85,091	85,504
Gross Unrealized, Gains	43,791	10,103
Gross Unrealized, Losses	(6,319)	(1,651)
Carrying value and fair value of equity securities	$ 122,563	$ 93,956