Fair Value of Assets and Liabilities (Tables)

6 Months Ended

Jun. 30, 2011

Fair Value of Assets and Liabilities (Tables) [Abstract]

Summary of Assets and Liabilities Recorded at Fair Market Value

	June 30, 2011								December 31, 2010
			Fair Value Measurements Using								Fair Value Measurements Using
	Fair Value		Level 1		Level 2		Level 3		Fair Value		Level 1		Level 2		Level 3
Assets
Short-term investments:
Certificates of deposit	$	229,532	$	229,532	$	—	$	—	$	221,706	$	221,706	$	—	$	—
U.S. dollar indexed bond funds		31,697		—		31,697		—		51,417		—		51,417		—
Assets held in a rabbi trust		8,400		8,400		—		—		8,163		8,163		—		—
Foreign exchange forward contracts		1,541		—		1,541		—		925		—		925		—
Contingent consideration on sale of business		—		—		—		—		2,030		—		—		2,030
Total	$	271,170	$	237,932	$	33,238	$	—	$	284,241	$	229,869	$	52,342	$	2,030
Liabilities
Deferred compensation	$	8,400	$	8,400	$	—	$	—	$	8,163	$	8,163	$	—	$	—
Foreign exchange forward contracts		1,241		—		1,241		—		4,060		—		4,060		—
Interest rate swaps		3,441		—		3,441		—		3,371		—		3,371		—
Total	$	13,082	$	8,400	$	4,682	$	—	$	15,594	$	8,163	$	7,431	$	—

Changes in fair value of the Company's level 3 assets

Balance as of January 1	$	2,030
Cash collections		(2,520	)
Fair value adjustments		490
Balance as of June 30	$	—

Fair value and carrying value of the Company's debt instruments

	June 30, 2011				December 31, 2010
			Carrying				Carrying
	Fair Value		Value		Fair Value		Value
Notes payable — current	$	43,900	$	43,900	$	15,038	$	15,038
Long-term debt		660,512		644,661		565,499		550,368
Total debt instruments	$	704,412	$	688,561	$	580,537	$	565,406