Acquisitions - Purchase Price Allocation for Acquisition (Detail) $ in Thousands	Jun. 30, 2015 USD ($)
SkyWave Mobile Communications Inc. [Member]
Business Acquisition [Line Items]
Cash	$ 110
Accounts receivable	14,028
Inventory	1,335
Other current assets	2,180
Property, plant and equipment	4,769
Intangible assets	67,214
Other noncurrent assets	6,108
Total identifiable assets acquired	95,744
Accounts payable and accrued expenses	9,987
Deferred revenues	1,117
Other liabilities	1,168
Deferred tax liabilities	17,527
Total liabilities assumed	29,799
Net identifiable assets acquired	65,945
Goodwill	56,758
Total preliminary purchase price	122,703
Insync, Inc [Member]
Business Acquisition [Line Items]
Cash	288
Accounts receivable	1,141
Other current assets	204
Deferred tax assets	2,342
Property, plant and equipment	51
Intangible assets	5,788
Other noncurrent assets	55
Total identifiable assets acquired	9,869
Accounts payable and accrued expenses	1,181
Deferred revenues	250
Deferred tax liabilities	2,342
Total liabilities assumed	3,773
Net identifiable assets acquired	6,096
Goodwill	5,546
Total preliminary purchase price	$ 11,642