Stock Incentive Plan (Schedule of Share-based Compensation, Unearned Compensation Related to RSU's) (Details) (Restricted Stock Units (RSUs), USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Changes In Unearned Compensation [Roll Forward]
Unearned compensation at beginning of year	$ 93,653	$ 57,315	$ 76,139
RSUs granted, net of cancellations	4,406	73,255	2,832
RSUs expensed	(22,881)	(25,728)	(26,303)
RSUs forfeiture adjustment	(1,973)	(11,189)	4,647
Unearned compensation at end of year	$ 73,205	$ 93,653	$ 57,315