Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2012

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis

			December 31, 2012
			Fair Value Measurements Using						Assets/Liabilities at Fair Value
			Level 1		Level 2			Level 3
			(in thousands)
Assets:
	Short-term investments (1)		$	6,018					$	6,018
Liabilities:
	Acquisition-related contingent consideration						$	23,711	$	23,711
	Interest rate swap agreements (2)				$	5,442			$	5,442
			December 31, 2011
			Fair Value Measurements Using						Assets/Liabilities at Fair Value
			Level 1		Level 2			Level 3
			(in thousands)
Assets:
	Short-term investments and available-for-sale
		securities (3)	$	22,270					$	22,270
Liabilities:
	Acquisition-related contingent consideration						$	25,617	$	25,617
(1)		Consists of highly liquid investments with original maturities in excess of three months.
(2)		Consists of interest rate swap agreements based on JIBAR and IBR whose value is determined using a pricing model with inputs that are observable in the market or can be derived principally from, or corroborated by, observable market data.
(3)		Consists of highly liquid investments with original maturities in excess of three months and available-for-sale securities traded in active markets.

Schedule Of Business Acquisitions Contingent Consideration Change [Table Text Block]

		2012		2011
Balance as of January 1	$	25,617	$	5,809
Additions		6,653		19,853
Payments		(15,716)		(5,742)
Change in fair value		6,329		5,634
Foreign currency translation adjustment		828		63
Balance as of December 31	$	23,711	$	25,617