Equity Awards - Restricted Shares Narrative (Details) (USD $)	3 Months Ended		9 Months Ended		3 Months Ended			3 Months Ended														12 Months Ended	3 Months Ended	12 Months Ended	9 Months Ended
	Sep. 30, 2014 Restricted Shares [Member]	Sep. 30, 2013 Restricted Shares [Member]	Sep. 30, 2014 Restricted Shares [Member]	Sep. 30, 2013 Restricted Shares [Member]	Mar. 31, 2014 Plan 1 [Member] Service-based restriced shares [Member]	Mar. 31, 2014 Plan 2 [Member] Service-based restriced shares [Member]	Mar. 31, 2014 Plan 3 [Member] number	Mar. 31, 2014 Plan 3 [Member] Restricted Shares [Member]	Mar. 31, 2014 Plan 3 [Member] Service-based restriced shares [Member]	Mar. 31, 2014 Plan 3 [Member] Performance-based restriced shares [Member]	Mar. 31, 2014 Plan 5 [Member] Service-based restriced shares [Member]	Mar. 31, 2014 Plan 5 [Member] Service-based restriced shares [Member] Non-employee independent director [Member]	Sep. 30, 2014 Plan 6 [Member] Service-based restriced shares [Member]	Mar. 31, 2014 Minimum [Member] Plan 2 [Member] Service-based restriced shares [Member]	Mar. 31, 2014 3 year EPS CAGR metric [Member] Plan 3 [Member] Performance-based restriced shares [Member]	Mar. 31, 2014 3 year EPS CAGR metric [Member] Minimum [Member] Plan 3 [Member] Performance-based restriced shares [Member]	Mar. 31, 2014 3 year EPS CAGR metric [Member] Maximum [Member] Plan 3 [Member] Performance-based restriced shares [Member]	Mar. 31, 2014 3 year ROIC metric [Member] [Member] Plan 3 [Member] Performance-based restriced shares [Member]	Mar. 31, 2014 3 year ROIC metric [Member] [Member] Minimum [Member] Plan 3 [Member] Performance-based restriced shares [Member]	Mar. 31, 2014 3 year ROIC metric [Member] [Member] Maximum [Member] Plan 3 [Member] Performance-based restriced shares [Member]	Mar. 31, 2013 2012 EPS growth metric [Member] Plan 4 [Member] Performance-based restriced shares [Member]	Dec. 31, 2013 2012 EPS growth metric [Member] Plan 4 [Member] Performance-based restriced shares [Member]	Mar. 31, 2014 2012 & 2013 EPS CAGR metric [Member] Plan 4 [Member] Performance-based restriced shares [Member]	Dec. 31, 2013 2012 & 2013 EPS CAGR metric [Member] Plan 4 [Member] Performance-based restriced shares [Member]	Sep. 30, 2014 Deferred Compensation, Share-based Payments [Member] Restricted Shares [Member] Non-employee independent director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares issued related to director fee deferrals																									7,409
Number of Unvested Restricted Shares Granted			352,082		23,226	40,837		243,124	121,562,000	121,562,000		20,832	600								72,576		16,054
Award requisite service period					3 years	1 year			3 years		1 year		1 year
ICP, Threshold target for granting stock awards														$ 20,000
Cash value of incentive plan						80.00%
Restriced shares value of incentive plan						20.00%
Award vesting period										3 years
Award percentage earned based on metric over the performance period															75.00%			25.00%			60.00%	60.00%	40.00%	40.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award percentage attained																					175.00%		125.00%
Number of performance metrics in restricted shares award type plan							2
Amount of shares earned % of target award																30.00%	250.00%		30.00%	200.00%
Unrecognized unvested restricted shares-based compensation expense	10,200,000		10,200,000
Weighted-average period for recognition of the unrecognized unvested restricted shares-based compensation expense			2 years 0 months
Restricted shares-based compensation expense	$ 2,300,000	$ 2,400,000	$ 6,700,000	$ 7,100,000