Long-term Debt - Credit Facility (Details)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Credit Facility [Member]
Debt Instrument [Line Items]
Total leverage ratio	4.73
Interest coverage ratio	3.64
Credit Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Total leverage ratio	6.75
Credit Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest coverage ratio	2.50
Term Loan Facility [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable interest rate	3.25%	4.00%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum	1.00%	1.00%
Term Loan Facility [Member] | Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable interest rate	2.25%	3.00%
Year 4 [Member] | Credit Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest coverage ratio	3.00
Year 4 [Member] | Credit Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Total leverage ratio	5.00