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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Allocation of Purchase Price (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Oct. 31, 2014	Oct. 25, 2013
Business Acquisition [Line Items]
Goodwill	$ 273,438us-gaap_Goodwill	$ 361,792us-gaap_Goodwill	$ 349,272us-gaap_Goodwill
Avionics Interface Technologies, LLC
Business Acquisition [Line Items]
Goodwill	10,516			10,516
Intangible assets	9,100			9,080
Other current assets				2,452
Non-current assets				359
Accounts payable and current liabilities				(1,164)
Total purchase price				21,243
ZTEC Instruments, Inc.
Business Acquisition [Line Items]
Goodwill					12,520
Intangible assets		4,900			4,870
Cash, cash equivalents and short term marketable securities					79
Other current assets					1,612
Non-current assets					1,757
Accounts payable and current liabilities					(1,811)
Long-term deferred tax liabilities					(1,719)
Total purchase price					$ 17,308