Income Taxes (Schedule Of Components Of Net Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current [Member]
Assets:
Accrued expenses		$ 23,298
Accounts receivable reserves		2,973
Deferred revenue		7,392
Inventory basis differences		3,292
Share-based compensation		2,565
Other		234
Net operating loss carryforwards		65
Total assets		39,819
Valuation allowance		(507)
Total assets, net of valuation allowance		39,312
Liabilities:
Other		(550)
Unrealized gains on foreign currency exchange contracts, interest rate swaps and investments		(882)
Total liabilities		(1,432)
Net deferred tax assets		37,880
Long-Term [Member]
Assets:
Accrued expenses	$ 22,145	5,329
Accounts receivable reserves	2,715
Deferred revenue	13,400	3,656
Inventory basis differences	3,959	293
Property-based differences	1,382	1,524
Share-based compensation	13,021	10,580
Other	678	361
Net operating loss carryforwards	4,182	4,059
Unrealized losses on foreign currency exchange contracts, interest rate swaps and investments	148	53
Total assets	61,630	25,855
Valuation allowance	(4,891)	(3,939)
Total assets, net of valuation allowance	56,739	21,916
Liabilities:
Accrued expenses	(143)
Accounts receivable reserves	(85)
Deferred revenue	(36)
Deferred instrument costs	(24,142)	(16,090)
Property-based differences	(43,159)	(35,079)
Intangible assst basis differences	(17,672)	(17,109)
Other	(507)	(1,460)
Unrealized gains on foreign currency exchange contracts, interest rate swaps and investments	(4,575)
Total liabilities	(90,319)	(69,738)
Net deferred tax (liabilities)	$ (33,580)	$ (47,822)