Selected Financial Statement Information (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Accounts receivable, net:
Trade accounts receivable	$ 132,782	$ 129,149
Allowance for doubtful accounts	(53)	(46)
Accounts receivable, net	132,729	129,103
Inventories:
Raw materials	26,798	39,821
Work-in-process	72,393	67,258
Finished goods	39,055	44,498
Total inventories	138,246	151,577
Other current assets:
Precious metals reclaim	24,402	19,035
Other	23,980	16,721
Other current assets	48,382	35,756
Property, plant and equipment, net:
Total property, plant and equipment, gross	923,612	877,116
Accumulated depreciation	(474,871)	(407,173)
Total property, plant and equipment, net	448,741	469,943
Accrued payroll:
Accrued payroll and taxes	13,670	12,602
Accrued paid time off and sabbatical	14,979	13,985
Accrued management incentive program	2,437	135
Self-insurance liability	2,168	1,797
Accrued payroll	33,254	28,519
Land
Property, plant and equipment, net:
Total property, plant and equipment, gross	19,691	19,691
Buildings
Property, plant and equipment, net:
Total property, plant and equipment, gross	94,766	93,184
Building and leasehold improvements
Property, plant and equipment, net:
Total property, plant and equipment, gross	31,012	28,619
Machinery and equipment
Property, plant and equipment, net:
Total property, plant and equipment, gross	664,737	577,262
Furniture and fixtures
Property, plant and equipment, net:
Total property, plant and equipment, gross	6,915	6,535
Computer equipment and software
Property, plant and equipment, net:
Total property, plant and equipment, gross	46,930	44,361
Computer equipment and software
Property, plant and equipment, net:
Total property, plant and equipment, gross	$ 59,561	$ 107,464