Acquisitions - Summary of Allocation of Purchase Price (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Jul. 19, 2016	Apr. 07, 2016
Business Acquisition [Line Items]
Goodwill	$ 3,685	$ 3,686
Total assets		5,843
Total liabilities		$ 1,525
Birdstep Technology AB [Member]
Business Acquisition [Line Items]
Cash and cash equivalents				$ 73
Accounts receivable				99
Income tax receivable				103
Prepaids and other current assets				311
Equipment and improvements				30
Intangible assets				670
Goodwill				1,991
Total assets				3,277
Accounts payable				223
Accrued liabilities				421
Deferred revenue				486
Deferred tax liability				147
Total liabilities				1,277
Total purchase price				$ 2,000
iMobileMagic - Mobile Experiences LDA [Member]
Business Acquisition [Line Items]
Cash and cash equivalents			$ 23
Short term investments			1
Accounts receivable			156
Prepaids and other current assets			8
Intangible assets			683
Goodwill			1,695
Total assets			2,566
Accounts payable			13
Accrued liabilities			64
Deferred tax liability			171
Total liabilities			248
Total purchase price			$ 2,318