Share-Based Payments (Options and Stock Appreciation Rights Outstanding) (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Available For Grant, Beginning Balance			291
Shares Available For Grant, Exercised			0
Shares Available For Grant, Forfeited			0
Shares Available For Grant, Expired			0
Shares Available For Grant, Granted			0
Shares Available For Grant, Ending Balance	291		291
Shares/Awards [Roll Forward]
Options Outstanding, Shares, Beginning Balance			82,468
Options Outstanding, Shares, Exercised			(41,650)
Options Outstanding, Shares, Forfeited			(400)
Options Outstanding, Shares, Expired			0
Options Outstanding, Shares, Granted			0
Options Outstanding, Shares, Ending Balance	40,418		40,418
Weighted-Average Exercise Price [Roll Forward]
Options Outstanding, Weighted-Average Exercise Price, Beginning Balance			$ 186.19
Options Outstanding, Weighted-Average Exercise Price, Exercised			$ 150.00
Options Outstanding, Weighted-Average Exercise Price, Forfeited			$ 255.13
Options Outstanding, Weighted-Average Exercise Price, Expired			$ 0.00
Options Outstanding, Weighted-Average Exercise Price, Granted			$ 0.00
Options Outstanding, Weighted-Average Exercise Price, Ending Balance	$ 222.80		$ 222.80
Compensation cost, liability balance	$ 4,600,000	$ 2,000,000	$ 4,600,000	$ 2,000,000
Total intrinsic value of options exercised			2,100,000	100,000
Total share-based liabilities paid	2,100,000	100,000	2,100,000	100,000
Cash received from exercise of options			400,000	400,000
Total fair value of shares vested	$ 0	$ 0
Stock Appreciation Rights [Member]
Shares/Awards [Roll Forward]
Options Outstanding, Shares, Beginning Balance			66,461
Options Outstanding, Shares, Exercised			(1,950)
Options Outstanding, Shares, Forfeited			(650)
Options Outstanding, Shares, Granted			0
Options Outstanding, Shares, Ending Balance	63,861		63,861
Weighted-Average Exercise Price [Roll Forward]
Options Outstanding, Weighted-Average Exercise Price, Beginning Balance			$ 125.03
Options Outstanding, Weighted-Average Exercise Price, Exercised			$ 114.64
Options Outstanding, Weighted-Average Exercise Price, Forfeited			$ 205.75
Options Outstanding, Weighted-Average Exercise Price, Granted			$ 0.00
Options Outstanding, Weighted-Average Exercise Price, Ending Balance	$ 124.52		$ 124.52