Estimated Fair Values of Assets Acquired and Liabilities Assumed for Drake Acquisition (Details) (Drake, USD $) In Thousands, unless otherwise specified	Dec. 02, 2011
Business Acquisition [Line Items]
Cash	$ 427
Current assets	4,245
Deferred tax asset	390
Property, plant and equipment	1,773
Goodwill	15,640
Other intangibles	5,810
Other assets	9
Current liabilities	(3,334)
Long-term deferred tax liability	(2,395)
Net assets acquired and liabilities assumed	22,565
as initially reported
Business Acquisition [Line Items]
Cash	427
Current assets	4,245
Deferred tax asset	390
Property, plant and equipment	1,773
Goodwill	15,237
Other intangibles	5,810
Other assets	9
Current liabilities	(3,334)
Long-term deferred tax liability	(2,395)
Net assets acquired and liabilities assumed	22,162
Measurement Period Adjustments
Business Acquisition [Line Items]
Cash	0
Current assets	0
Deferred tax asset	0
Property, plant and equipment	0
Goodwill	403
Other intangibles	0
Other assets	0
Current liabilities	0
Long-term deferred tax liability	0
Net assets acquired and liabilities assumed	$ 403