Long-Term Debt (Details) (USD $)			6 Months Ended						6 Months Ended		1 Months Ended
	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2013 STARS [Member]	May 21, 2011 Senior Note June 2021 [Member]	May 23, 2011 Credit Agreement [Member]	May 23, 2011 Revolving Line of Credit March 2016 [Member]	May 23, 2011 Multi Currency Sub Facility [Member]	May 23, 2011 Letter Of Credit Sub Facility [Member]	Jun. 30, 2013 Term Loan due March 2016 [Member]	May 23, 2011 Term Loan due March 2016 [Member]	Mar. 31, 2016 Acquisition Notes [Member] Non Interest Bearing Acquisition Note [Member]	Mar. 31, 2014 Acquisition Notes [Member] Non Interest Bearing Acquisition Note [Member]	Jun. 30, 2013 Acquisition Notes [Member] Non Interest Bearing Acquisition Note [Member]	Dec. 31, 2012 Acquisition Notes [Member] Non Interest Bearing Acquisition Note [Member]	Jun. 30, 2013 Acquisition Notes [Member] Non Interest Bearing Acquisition Note [Member] STARS [Member]	Jun. 30, 2013 Notes Payable to Banks [Member] Senior Note June 2021 [Member]	Dec. 31, 2012 Notes Payable to Banks [Member] Senior Note June 2021 [Member]	Jun. 30, 2013 Notes Payable to Banks [Member] Senior Debentures August 2014 [Member]	Dec. 31, 2012 Notes Payable to Banks [Member] Senior Debentures August 2014 [Member]	Jun. 30, 2013 Notes Payable to Banks [Member] Senior Debentures April 2028 [Member]	Dec. 31, 2012 Notes Payable to Banks [Member] Senior Debentures April 2028 [Member]	Jun. 30, 2013 Line of Credit [Member] Revolving Line of Credit March 2016 [Member]	Dec. 31, 2012 Line of Credit [Member] Revolving Line of Credit March 2016 [Member]	Jun. 30, 2013 Bank Loans [Member] Term Loan due March 2016 [Member]	Dec. 31, 2012 Bank Loans [Member] Term Loan due March 2016 [Member]	Jun. 30, 2013 Notes Payable, Other Payables [Member] Various Interest Rate Loans [Member]	Dec. 31, 2012 Notes Payable, Other Payables [Member] Various Interest Rate Loans [Member]
Long-Term Debt
Total long-term Debt	$ 788,812,000	$ 792,426,000											$ 9,011,000	$ 8,753,000		$ 393,000,000	$ 393,000,000	$ 825,000	$ 825,000	$ 59,645,000	$ 59,645,000	$ 50,000,000	$ 50,000,000	$ 275,625,000	$ 280,000,000	$ 706,000	$ 203,000
Less current portion of long-term debt	5,081,000	102,000
Long-term debt, net of current portion	783,731,000	792,324,000
Debt instrument, amount of installment											5,000,000	5,000,000
Debt instrument, stated interest rate percentage				7.25%												7.25%		5.70%		7.55%		1.90%		3.00%	0.00%
Debt instrument, face amount				400,000,000											15,000,000
Repayments of debt									4,400,000
Term facility, maximum borrowing capacity					1,400,000,000	550,000,000	100,000,000	50,000,000		350,000,000
Term facility, length of term									5 years
Accrued interest expense	3,800,000	4,100,000
Payments to acquire interest in joint venture			$ 20,000,000