Debt and Financing (Details)		6 Months Ended			12 Months Ended
	Jun. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Jun. 27, 2016 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 1,060,800,000	$ 1,060,800,000
Premium/(Discount), Debt	(3,600,000)	(3,600,000)
Debt Issuance Cost	(12,800,000)	(12,800,000)
Book Value	1,044,400,000	1,044,400,000
Book Value, Current Maturities	(16,400,000)	(16,400,000)				$ (15,900,000)
Par Value, Excluding Current Maturities	1,044,400,000	1,044,400,000
Debt Instrument, Unamortized Discount (Premium), Net, Noncurrent Maturities	3,600,000	3,600,000
Book Value, Excluding Current Maturities	1,028,000,000	1,028,000,000				1,046,500,000
Debt Instrument, Borrowing Base Cash Release As Percent Of Collateral	0.10		$ 0.15
Cash and cash equivalents	243,500,000	243,500,000				173,800,000	$ 196,000,000	$ 171,100,000
Operating leases, future minimum payments, remainder of fiscal year	47,300,000	47,300,000
Operating leases, future minimum payments due	299,800,000	299,800,000
Acquisition of property and equipment		(47,300,000)		$ (42,600,000)
Carrying Amount [Member]
Debt Instrument [Line Items]
Long-term Debt, Fair Value	1,044,400,000	1,044,400,000				1,062,400,000
Fair Value [Member]
Debt Instrument [Line Items]
Long-term Debt, Fair Value	977,000,000	977,000,000				979,600,000
Term Loan
Debt Instrument [Line Items]
Long-term Debt, Gross	682,500,000	682,500,000
Premium/(Discount), Debt	(3,600,000)	(3,600,000)
Debt Issuance Cost	(10,600,000)	(10,600,000)
Book Value	668,300,000	668,300,000
Debt Instrument, Gross, Current Maturities	(7,000,000)	(7,000,000)
Premium/(Discount), Current Maturities	0	0
Deferred Finance Costs, Current, Net	0	0
Book Value, Current Maturities	$ (7,000,000)	$ (7,000,000)
Stated Interest Rate	8.00%	8.00%
Average Effective Interest Rate	8.20%	8.20%
Term Loan | Carrying Amount [Member]
Debt Instrument [Line Items]
Long-term Debt, Fair Value	$ 668,300,000	$ 668,300,000				669,000,000
Term Loan | Fair Value [Member]
Debt Instrument [Line Items]
Long-term Debt, Fair Value	621,600,000	621,600,000				594,600,000
Line of Credit [Member] | 2014 ABL Facility Credit Agreement [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	0	0
Premium/(Discount), Debt	0	0
Debt Issuance Cost	0	0
Book Value	0	0
Borrowing base	435,500,000	435,500,000
Line of credit facility, total cash and availability	78,900,000	78,900,000
Secured Second A&R CDA [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	30,500,000	30,500,000
Premium/(Discount), Debt	0	0
Debt Issuance Cost	(200,000)	(200,000)
Book Value	$ 30,300,000	$ 30,300,000
Average Effective Interest Rate	7.30%	7.30%
Stated Interest Rate, Minimum		3.30%
Stated Interest Rate, Maximum		18.30%
Unsecured Second A&R CD [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 73,200,000	$ 73,200,000
Premium/(Discount), Debt	0	0
Debt Issuance Cost	(500,000)	(500,000)
Book Value	$ 72,700,000	$ 72,700,000
Average Effective Interest Rate	7.30%	7.30%
Stated Interest Rate, Minimum		3.30%
Stated Interest Rate, Maximum		18.30%
Lease Financing Obligations [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 274,600,000	$ 274,600,000
Premium/(Discount), Debt	0	0
Debt Issuance Cost	(1,500,000)	(1,500,000)
Book Value	273,100,000	273,100,000
Debt Instrument, Gross, Current Maturities	(9,400,000)	(9,400,000)
Premium/(Discount), Current Maturities	0	0
Deferred Finance Costs, Current, Net	0	0
Book Value, Current Maturities	$ (9,400,000)	$ (9,400,000)
Average Effective Interest Rate	12.00%	12.00%
Stated Interest Rate, Minimum		9.00%
Stated Interest Rate, Maximum		18.20%
Lease Financing Obligations [Member] | Carrying Amount [Member]
Debt Instrument [Line Items]
Long-term Debt, Fair Value	$ 273,100,000	$ 273,100,000				276,300,000
Lease Financing Obligations [Member] | Fair Value [Member]
Debt Instrument [Line Items]
Long-term Debt, Fair Value	260,900,000	260,900,000				282,900,000
Letter of Credit [Member] | 2014 ABL Facility Credit Agreement [Member]
Debt Instrument [Line Items]
Letters of credit outstanding, amount	356,600,000	356,600,000
10 percent of Borrowing Base	43,600,000	43,600,000
10 percent of line cap					$ 45,000,000
Other Debt Obligations [Member] | Carrying Amount [Member]
Debt Instrument [Line Items]
Long-term Debt, Fair Value	103,000,000	103,000,000				117,100,000
Other Debt Obligations [Member] | Fair Value [Member]
Debt Instrument [Line Items]
Long-term Debt, Fair Value	94,500,000	$ 94,500,000				$ 102,100,000
Credit Agreement Amendment, September 2014 [Member]
Debt Instrument [Line Items]
Maximum Total Leverage Ratio, June 30, 2016		3.75
Maximum Total Leverage Ratio, September 30, 2016		3.75
Maximum Total Leverage Ratio, December 31, 2016		3.5
Maximum Total Leverage Ratio, March 31, 2017		3.25
Maximum Total Leverage Ratio, June 30, 2017		3.25
Maximum Total Leverage Ratio, September 30, 2017		3.25
Maximum Total Leverage Ratio, December 31, 2017 and thereafter		3.00
Debt Instrument, Total Leverage Ratio					3.32
2014 ABL Facility Credit Agreement [Member]
Debt Instrument [Line Items]
Amount able to be drawn		$ 35,300,000
2014 ABL Facility Credit Agreement [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Line of credit facility, total cash and availability	278,800,000.0	278,800,000.0
Revenue Equipment [Member]
Debt Instrument [Line Items]
Operating lease commitment	$ 58,400,000	$ 58,400,000
Operating lease term		5 years
London Interbank Offered Rate (LIBOR) [Member] | Term Loan
Debt Instrument [Line Items]
Floor interest rate	1.00%	1.00%
Basis Spread On Variable Rate, Total Leverage Ratio Less Than 3.25		7.00%
London Interbank Offered Rate (LIBOR) [Member] | ABL Facility [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%		2.25%