Debt Carrying and Estimated Fair Value Table (Details) (USD $) In Thousands, unless otherwise specified	1 Months Ended
	Nov. 02, 2012	Sep. 30, 2012		Dec. 31, 2011		Sep. 30, 2011
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		4.25%				4.25%
Total long-term debt		$ 546,213		$ 555,705		$ 607,635
Less current portion		(40,903)		(16,774)		(16,774)
7.5% senior notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		7.50%
Carrying value		106,438	[1]	106,438	[1]	156,438	[1]
Estimated fair value		105,000	[1]	107,000	[1]	158,000	[1]
7.5% Senior Notes callable amount	101.25%
4.25% Convertible senior notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		4.25%
Carrying value (convertible debt)		150,542	[1]	143,367	[1]	141,117	[1]
Estimated fair value		175,000	[1]	172,000	[1]	176,000	[1]
Credit facility revolving loan [Member]
Debt Instrument [Line Items]
Carrying value		20,000	[2]	0	[2]
Estimated fair value		19,000	[2]	0	[2]
Credit facility term loan [Member]
Debt Instrument [Line Items]
Carrying value		309,375	[2]	321,750	[2]	325,875	[2]
Estimated fair value		300,000	[2]	321,000	[2]	324,000	[2]
Other [Member]
Debt Instrument [Line Items]
Carrying value (other)		761	[2]	924	[2]	979	[2]
Estimated fair value		$ 700	[2]	$ 900	[2]	$ 900	[2]

[1] The fair value of the parent company debt is based on observable inputs, which include quoted prices for similar assets or liabilities in an active market and market-corroborated inputs (Level 2). See also Note 8 for discussion of fair value.

[2] Credit facilities and other subsidiary debt may be traded on the secondary loan market, and the fair value of the Term Loan is based on either the last available trading price, if recent, or trading prices of comparable debt (Level 3). See also Note 8 for discussion of fair value.