Condensed Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Current Assets:
Cash and cash equivalents	$ 230.9	$ 114.5
Accounts receivable, net	192.5	182.3
Deferred income taxes	9.2	9.1
Prepaid expenses and other assets	32.1	43.0
Total current assets	464.7	348.9
Investment in terminal joint venture	63.2	57.6
Property and equipment, net	706.3	735.4
Goodwill and intangible assets, net	30.3	31.2
Other long-term assets	96.3	75.2
Total assets	1,360.8	1,248.3
Current Liabilities:
Current portion of long-term debt	17.1	12.5
Accounts payable	126.8	124.0
Payroll and vacation benefits	15.5	16.9
Self-insured liabilities	19.6	15.1
Accrued and other liabilities	25.8	32.1
Total current liabilities	204.8	200.6
Long-term Liabilities:
Long-term debt	360.4	273.6
Deferred income taxes	324.1	326.1
Employee benefit plans	67.8	74.4
Self-insured claims and other liabilities	36.8	35.4
Total long-term liabilities	789.1	709.5
Commitments and Contingencies (Note 7)
Shareholders' Equity:
Capital stock	32.1	32.1
Additional paid in capital	267.4	261.9
Accumulated other comprehensive loss	(22.0)	(23.5)
Retained earnings	89.4	67.7
Total shareholders' equity	366.9	338.2
Total liabilities and shareholders' equity	$ 1,360.8	$ 1,248.3