Fair Value Of Financial Instruments (Narrative) (Details) (USD $)		3 Months Ended			12 Months Ended	3 Months Ended
	Mar. 31, 2014 Senior Notes [Member] Unsecured Debt [Member] 4.875% Senior Notes [Member]	Mar. 31, 2014 Earn-out Arrangements [Member]	Mar. 31, 2013 Earn-out Arrangements [Member]	Mar. 31, 2014 Earn-out Arrangements [Member] Foreign Currency Translation Adjustments [Member]	Dec. 31, 2013 Earn-out Arrangements [Member] Foreign Currency Translation Adjustments [Member]	Mar. 31, 2014 Level 1 [Member] Senior Notes [Member] Unsecured Debt [Member] Total Senior And Senior Convertible Notes [Member]	Mar. 31, 2014 Level 1 [Member] Cash Surrender Value [Member]	Mar. 31, 2014 Level 3 [Member] Earn-out Arrangements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Non-Recurring Basis [Line Items]
Fair value measurements, valuation techniques						The estimated fair values of the Company’s 4.875% Senior Notes, 2009 Convertible Notes and 2011 Convertible Notes are based on quoted market prices, a Level 1 input.	Cash surrender values of life insurance policies are based on current cash surrender values as quoted by insurance carriers.	The fair value of such acquisition-related contingent consideration is based on management’s estimates and entity-specific assumptions and is evaluated on an on-going basis.
Debt instrument, interest rate	4.875%
Additions from new business combinations, acquisition-related contingent consideration		$ 8,700,000	$ 0
Payments of acquisition-related contingent consideration		0	600,000
Foreign currency translation adjustments included in other comprehensive income, acquisition-related contingent consideration				$ 1,400,000	$ 400,000