LONG TERM DEBT (DETAILS) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Debt Instrument [Line Items]
Current portion long term debt	$ 181,000		$ 181,000		$ 169,145,000
Long-term debt	594,739,000		594,739,000		181,000
Principal Amount Payment			3,000
Amortization of Debt Discount (Premium)			5,327,000	0
Amortization of deferred financing fees			891,000	0
Interest Expense, Debt	7,158,000	1,267,000	12,240,000	3,453,000
Convertible Debt Fair Value Disclosures	789,700,000		789,700,000		202,500,000
Convertible Senior Notes Due 2032 [Member]
Debt Instrument [Line Items]
Long-term Debt	168,926,000		168,926,000		169,145,000
Stated Interest Rate	2.50%		2.50%
Stated Contingent Interest Rate	0.50%		0.50%
Contingent Interest Payable	300,000		300,000
Contingent Interest Rate Terms	The Company also agreed to pay contingent interest at a rate equal to 0.5% per annum during any six-month period, with the initial six-month period commencing June 4, 2007, if the average trading price of the 2.5% Notes reaches certain thresholds.
Debt Instrument Convertible Terms Of Conversion Feature	The 2.5% Notes are convertible, at the holders’ option, prior to the maturity date into shares of the Company’s Class A common stock in the following circumstances: during any quarter commencing after June 30, 2002, if the closing price of the Company’s Class A common stock over a specified number of trading days during the previous quarter, including the last trading day of such quarter, is more than 110% of the conversion price of the 2.5% Notes, or $31.96. The 2.5% Notes are initially convertible at a conversion price of $29.05 per share, which is equal to a conversion rate of approximately 34.4234 shares per $1,000 principal amount of 2.5% Notes, subject to adjustment; if the Company has called the 2.5% Notes for redemption; during the five trading day period immediately following any nine consecutive day trading period in which the trading price of the 2.5% Notes per $1,000 principal amount for each day of such period was less than 95% of the product of the closing sale price of the Company’s Class A common stock on such days multiplied by the number of shares of the Company’s Class A common stock issuable upon conversion of $1,000 principal amount of the 2.5% Notes; or upon the occurrence of specified corporate transactions.
Debt Instrument Fee Amount	12,600,000		12,600,000
Principal Amount Payment				0
Deferred Tax Liability Convertible Debt					62,500,000
Interest Expense, Debt, Excluding Amortization	1,056,000	1,057,000	3,170,000	3,171,000
Contingent Interest Expense	211,000	209,000	281,000	280,000
Interest Expense, Debt	1,267,000	1,266,000	3,451,000	3,451,000
Convertible Senior Notes Due 2033 [Member]
Debt Instrument [Line Items]
Long-term Debt	181,000		181,000		181,000
Stated Interest Rate	1.50%		1.50%
Stated Contingent Interest Rate	0.50%		0.50%
Contingent Interest Rate Terms	The Company will also pay contingent interest at a rate of 0.5% per annum during any six-month period, with the initial six-month period commencing June 4, 2008, if the average trading price of the 1.5% Notes reaches certain thresholds.
Debt Instrument Convertible Terms Of Conversion Feature	The remaining 1.5% Notes are convertible, at the holders’ option, prior to the maturity date into shares of the Company’s Class A common stock in the following circumstances: during any quarter commencing after September 30, 2003, if the closing price of the Company’s Class A common stock over a specified number of trading days during the previous quarter, including the last trading day of such quarter, is more than 120% of the conversion price of the 1.5% Notes, or $46.51. The 1.5% Notes are initially convertible at a conversion price of $38.76 per share, which is equal to a conversion rate of approximately 25.7998 shares per $1,000 principal amount of 1.5% Notes, subject to adjustment; if the Company has called the 1.5% Notes for redemption; during the five trading day period immediately following any nine consecutive day trading period in which the trading price of the 1.5% Notes per $1,000 principal amount for each day of such period was less than 95% of the product of the closing sale price of the Company’s Class A common stock on such days multiplied by the number of shares of the Company’s Class A common stock issuable upon conversion of $1,000 principal amount of the 1.5% Notes; or upon the occurrence of specified corporate transactions.
Debt Instrument Fee Amount	5,100,000		5,100,000
Deferred Tax Liability Convertible Debt	58,000		58,000
Interest Expense, Debt, Excluding Amortization	1,000	1,000	2,000	2,000
Interest Expense, Debt	1,000	1,000	2,000	2,000
Convertible Senior Notes Due 2017 [Member]
Debt Instrument [Line Items]
Debt Instrument Face Amount	500,000,000		500,000,000		0
Debt Instrument, Unamortized Discount	(74,187,000)		(74,187,000)		0
Long-term Debt	425,813,000		425,813,000		0
Stated Interest Rate	1.375%		1.375%
Debt Instrument Convertible Terms Of Conversion Feature	The 1.375% Notes are convertible, at the holders’ option, prior to the close of business on the business day immediately preceding March 1, 2017, into shares of the Company’s Class A common stock in the following circumstances: during any calendar quarter commencing after the calendar quarter ending on September 30, 2012, if the closing price of the Company’s Class A common stock over a specified number of trading days during the previous quarter, including the last trading day of such quarter, is more than 130% of the conversion price of the 1.375% Notes in effect on each applicable trading day; during the five consecutive trading day period immediately following any ten consecutive trading day period in which the trading price of the 1.375% Notes per $1,000 principal amount for each such trading day was less than 98% of the product of the closing sale price of the Company’s Class A common stock on such days and the then-current conversion rate of $1,000 principal amount of the 1.375% Notes; or upon the occurrence of specified corporate transactions.
Interest Expense, Debt, Excluding Amortization	1,718,000	0	2,569,000	0
Amortization of Debt Discount (Premium)	3,577,000	0	5,327,000	0
Amortization of deferred financing fees	595,000	0	891,000	0
Interest Expense, Debt	$ 5,890,000	$ 0	$ 8,787,000	$ 0