Long-Term Obligations (Details 2)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Interest rate description	the base rate or the Eurodollar rate plus a margin of 1.50%
Senior Notes [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Effective interest rate (percentage)	1.67%	1.92%
Federal fund rate [Member] | Senior Notes [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Basis spread on variable rate	0.05%
Eurodollar [Member] | Senior Notes [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Basis spread on variable rate	1.00%
Tier One [Member] | Minimum [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Consolidated Leverage Ratio	4
Tier Two [Member] | Maximum [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Consolidated Leverage Ratio	4
Tier Two [Member] | Minimum [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Consolidated Leverage Ratio	3.25
Tier Three [Member] | Maximum [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Consolidated Leverage Ratio	3.25
Tier Three [Member] | Minimum [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Consolidated Leverage Ratio	2.50
Tier Four [Member] | Maximum [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Consolidated Leverage Ratio	2.5
Tier Four [Member] | Minimum [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Consolidated Leverage Ratio	1.75
Tier Five [Member] | Maximum [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Consolidated Leverage Ratio	1.75
Tier Five [Member] | Minimum [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Consolidated Leverage Ratio	1.00
Tier Six [Member] | Maximum [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Consolidated Leverage Ratio	1.00
Credit Agreement [Member] | Tier One [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Commitment Fee	0.45%
Credit Agreement [Member] | Tier One [Member] | Eurodollar [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Applicate margin for borrowings	2.25%
Credit Agreement [Member] | Tier One [Member] | Base rate [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Applicate margin for borrowings	1.25%
Credit Agreement [Member] | Tier Two [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Commitment Fee	0.40%
Credit Agreement [Member] | Tier Two [Member] | Eurodollar [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Applicate margin for borrowings	2.00%
Credit Agreement [Member] | Tier Two [Member] | Base rate [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Applicate margin for borrowings	1.00%
Credit Agreement [Member] | Tier Three [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Commitment Fee	0.35%
Credit Agreement [Member] | Tier Three [Member] | Eurodollar [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Applicate margin for borrowings	1.75%
Credit Agreement [Member] | Tier Three [Member] | Base rate [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Applicate margin for borrowings	0.75%
Credit Agreement [Member] | Tier Four [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Commitment Fee	0.30%
Credit Agreement [Member] | Tier Four [Member] | Eurodollar [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Applicate margin for borrowings	1.50%
Credit Agreement [Member] | Tier Four [Member] | Base rate [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Applicate margin for borrowings	0.50%
Credit Agreement [Member] | Tier Five [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Commitment Fee	0.25%
Credit Agreement [Member] | Tier Five [Member] | Eurodollar [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Applicate margin for borrowings	1.25%
Credit Agreement [Member] | Tier Five [Member] | Base rate [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Applicate margin for borrowings	0.25%
Credit Agreement [Member] | Tier Six [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Commitment Fee	0.25%
Credit Agreement [Member] | Tier Six [Member] | Eurodollar [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Applicate margin for borrowings	1.00%
Credit Agreement [Member] | Tier Six [Member] | Base rate [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Applicate margin for borrowings	0.00%
Revolving line of credit [Member]
Schedule Of Percentage Margin For Eurodollar Rate Loans And Commitment Fee [Line Items]
Effective interest rate (percentage)	1.67%