Related-Party Transactions (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Related Party Transactions
Revenue from related party	$ 190.6	$ 164.0	$ 218.4
Expenses from business transactions with unconsolidated affiliates	0.1	0.1	0.9
Accounts receivable from affiliated entities	87.1	68.7
Accounts payable to affiliated entities	6.4	3.2
Long-term payables with affiliated entities	0.8	0.8
Mr. Linn | LINN
Related Party Transactions
Revenue from related party	3.2	12.5
Accounts receivable from affiliated entities	0.2	1.9
Mr. Crane | CCG
Related Party Transactions
Accounts payable to affiliated entities	1.4	1.4
Amount paid to related party for services provided	39.4	4.2
Key employees, including Messrs. Isenberg and Petrello
Related Party Transactions
Premium payments to date related to life insurance policies	6.5
Cash surrender value included in other long-term assets	$ 5.9	$ 5.8