Senior Debt (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Debt Instrument [Line Items]
Senior Credit Facility Maximum Amount		$ 900,000,000
Term loan, maximum facility		225,000,000	$ 225,000,000
Term loan, amount outstanding		221,063,000	223,313,000
Term loan, amount available		0	0
Revolving facility, maximum facility		675,000,000
Senior credit facilities, maximum facility		900,000,000	900,000,000
Senior credit facilities, amount outstanding		411,063,000	478,313,000
Senior credit facilities, amount available		390,300,000	315,600,000
Debt facilities, maximum facility		920,000,000	920,000,000
Debt facilities, amount outstanding		425,633,000	492,813,000
Debt facilities, amount available		395,730,000	321,100,000
Letters of credit, amount outstanding		$ 94,700,000	104,400,000
Line of Credit Facility, Interest Rate Description		Borrowings under the Revolving Facility bear interest at varying rates
Commitment fee percentage		0.45%
Senior Credit Facilities, Additional Amount Allowed		$ 250,000,000
Debt Instrument, Covenant, Total Leverage Ratio Maximum, Ability to Repurchase Stock, Notes, or Pay Dividends		2.5
Schedule Maturity Dates (Table Details) [Abstract]
2016		$ 16,820,000
2017		2,250,000
2018		2,250,000
2019		192,250,000
2020		2,250,000
Thereafter		209,813,000
Long-term Debt		425,633,000
Debt Instrument, Covenant, Total Leverage Ratio Maximum, Ability to Repurchase Stock, Notes, or Pay Dividends, Dividend Exception Amount		$ 20,000,000
Initial Borrowing in Term Loans	$ 225,000,000
Initial Borrowing in Revolving Debt	$ 100,000,000
Long-term Debt, Maturities, Repayment Terms		25000
Term Loan, Frequency of Periodic Payment		quarterly
Term Loan, Periodic Payment, Principal		$ 562,500
Event of default - 3rd party ownership % of our voting stock		35.00%
Event of default - judgment not satisfied or bonded pending appeal		$ 50,000,000
Event of default - maximum period allowed for pending judgment		30
Financial Covenants Ratios (Table Details) [Abstract]
Required consolidated leverage ratio, maximum		4.25
Actual consolidated leverage ratio		3.13
Required Consolidated Senior Secured Leverage Ratio, Maximum		2.75
Actual Consolidated Senior Secured Leverage Ratio		1.26
Required Consolidated Fixed Charge Coverage Ratio, Minimum		1.75
Actual fixed charge coverage ratio		1.87
Covenants [Abstract]
Consolidated funded debt outstanding		$ 933,000,000
Consolidated EBITDA		298,200,000
Covenant limitation incur additional debt in excess of		25,000,000
Consolidated senior secured debt outstanding		375,700,000
Adjusted Consolidated EBITDA		537,400,000
Consolidated fixed charges		$ 287,900,000
Minimum [Member]
Debt Instrument [Line Items]
Commitment fee percentage		0.30%
Maximum [Member]
Debt Instrument [Line Items]
Commitment fee percentage		0.50%
Eurodollar Rate [Member]
Debt Instrument [Line Items]
Description of variable rate basis		Eurodollar
Eurodollar Rate [Member] | Minimum [Member]
Debt Instrument [Line Items]
Basis margin on variable rate		1.50%
Eurodollar Rate [Member] | Maximum [Member]
Debt Instrument [Line Items]
Basis margin on variable rate		2.75%
Prime Rate [Member]
Debt Instrument [Line Items]
Description of variable rate basis		prime
Prime Rate [Member] | Minimum [Member]
Debt Instrument [Line Items]
Basis margin on variable rate		0.50%
Prime Rate [Member] | Maximum [Member]
Debt Instrument [Line Items]
Basis margin on variable rate		1.75%
Term Loan [Member]
Debt Instrument [Line Items]
Maturity date		Mar. 19, 2021
Margin on Eurodollar rate, actual		3.00%
Margin on ABR rate, actual		2.00%
Schedule Maturity Dates (Table Details) [Abstract]
2016		$ 2,250,000
2017		2,250,000
2018		2,250,000
2019		2,250,000
2020		2,250,000
Thereafter		209,813,000
Long-term Debt		$ 221,063,000
Revolving Facility [Member]
Debt Instrument [Line Items]
Maturity date		Mar. 19, 2019
Revolving facility, maximum facility		$ 675,000,000	675,000,000
Revolving facility, amount outstanding		190,000,000	255,000,000
Revolving facility, amount available		$ 390,300,000	315,600,000
Margin on Eurodollar rate, actual		2.25%
Margin on ABR rate, actual		1.25%
Schedule Maturity Dates (Table Details) [Abstract]
2016		$ 0
2017		0
2018		0
2019		190,000,000
2020		0
Thereafter		0
Long-term Debt		$ 190,000,000
Line of Credit [Member]
Debt Instrument [Line Items]
Maturity date		Aug. 21, 2016
Revolving facility, maximum facility		$ 20,000,000	20,000,000
Revolving facility, amount outstanding		14,570,000	14,500,000
Revolving facility, amount available		5,430,000	$ 5,500,000
Schedule Maturity Dates (Table Details) [Abstract]
2016		14,570,000
2017		0
2018		0
2019		0
2020		0
Thereafter		0
Long-term Debt		$ 14,570,000
Line of Credit [Member] | Minimum [Member]
Schedule Maturity Dates (Table Details) [Abstract]
Interest rate of senior notes		2.00%