Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2011 Country	Dec. 31, 2010	Dec. 31, 2009
Significant Accounting Policies [Line Items]
Number of Countries in which Entity Operates	120
Cost of inventories determined by LIFO method	$ 7,100,000	$ 6,900,000
Cost of inventories determined by LIFO method, percentage of total inventories	2.00%	2.20%
Cost of inventories determined by LIFO method, amount of increase if FIFO method was used	5,600,000	4,900,000
Foreign currency translation adjustments recorded in AOCI net of tax effects	(208,009,000)	(54,111,000)	53,574,000
Foreign currency translation adjustments, gains	96,300,000	294,600,000
Foreign currency translation adjustments, losses	133,500,000	124,000,000
Net exchange gains(losses)	(2,900,000)	(3,300,000)	300,000
Precious metal content of sales	205,129,000	189,257,000	168,712,000
R&D costs included in selling, general and administrative expenses	66,700,000	49,400,000	50,300,000
Accumulated Translation Adjustment
Significant Accounting Policies [Line Items]
Foreign currency translation adjustments recorded in AOCI net of tax effects	(9,600,000)	(16,300,000)
Foreign currency translation adjustments recorded in AOCI net of tax effects	167,500,000	158,700,000	143,000,000
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges
Significant Accounting Policies [Line Items]
Foreign currency translation adjustments recorded in AOCI net of tax effects	(200,100,000)	(33,200,000)
Precious Metal Content
Significant Accounting Policies [Line Items]
Precious metal content of sales	205,100,000	189,200,000	168,700,000
Dental Products
Significant Accounting Policies [Line Items]
Percentage of sales, professional dental products	93.00%		97.00%
Building
Significant Accounting Policies [Line Items]
Estimated useful life (in years)	40
Machinery and equipment
Significant Accounting Policies [Line Items]
Estimated useful life, minimum (in years)	4
Estimated useful life, maximum (in years)	15
Trade Accounts Receivable
Significant Accounting Policies [Line Items]
Allowance for doubtful accounts	15,000,000	8,800,000
Write-off of Provision for doubtful accounts	1,400,000	2,600,000
Provision for doubtful accounts	(500,000)	200,000
Trade Accounts Receivable Astra [Member]
Significant Accounting Policies [Line Items]
Allowance for doubtful accounts	7,400,000
Notes Receivable
Significant Accounting Policies [Line Items]
Write-off of Provision for doubtful accounts	900,000
Allowance for Notes, Loans and Financing Receivable, Current	900,000	800,000
Provision for doubtful accounts	$ 1,000,000	$ 700,000