Stock Option and Incentive Plan Stock Option and Incentive Plan and Stock Purchase Plan (Tables)

12 Months Ended

Dec. 31, 2013

Stock Option and Incentive Plan and Stock Purchase Plan [Abstract]

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

	Shares		Weighted Average Exercise Price
Outstanding at December 31, 2010	324,938		$	32.65
Granted	146,844		$	92.71
Exercised	(316,159	)	$	32.63
Canceled	—		$	—
Outstanding at December 31, 2011	155,623		$	89.35
Granted	186,007		$	107.23
Exercised	(22,823	)	$	72.42
Canceled	(24,280	)	$	100.15
Outstanding at December 31, 2012	294,527		$	101.06
Granted	252,220		$	104.50
Exercised	—		$	—
Canceled	—		$	—
Special dividend adjustment	12,076		$	100.44
Outstanding at December 31, 2013	558,823		$	100.43

Schedule of Stock Options Outstanding [Table Text Block]

The following table summarizes information about stock options outstanding at December 31, 2013:

Options Outstanding						Options Exercisable
Exercise Prices		Number Outstanding at 12/31/13	Remaining Contractual Life	Exercise Price		Number Exercisable at 12/31/13	Exercise Price
$	90.71	131,837	7.1 years	$	90.71	80,240	$	90.71
$	99.94	51,971	9.3 years	$	99.94	—	$	—
$	102.83	205,821	9.1 years	$	102.83	48,026	$	102.83
$	105.25	169,194	8.1 years	$	105.25	71,602	$	105.25