Bank Credit Agreements and Other Short-Term and Long-Term Debt (Interest expense) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Debt Instruments [Abstract]
Notes Contractual Interest Expense		$ 2,267	$ 3,077
Amortization of discount on convertible senior notes	0	6,032	7,656
Amortization Of Debt Issuance Cost		412	549
Total		$ 8,711	$ 11,282