Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) (Customer Concentration Risk [Member])	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended			12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended
	Sep. 30, 2014 Huawei Technologies [Member] Revenue [Member]	Sep. 30, 2014 Huawei Technologies [Member] Revenue [Member]	Sep. 30, 2014 Ciena Corporation [Member] Revenue [Member]	Sep. 30, 2014 Ciena Corporation [Member] Revenue [Member]	Sep. 30, 2014 Company Top Ten Customers [Member] Revenue [Member]	Sep. 30, 2014 Company Top Ten Customers [Member] Revenue [Member]	Sep. 30, 2014 Alcatel-Lucent SA [Member] Revenue [Member]	Sep. 30, 2014 Customer One [Member] Accounts Receivable [Member]	Dec. 31, 2013 Customer One [Member] Accounts Receivable [Member]	Sep. 30, 2014 Customer Two[Member] Accounts Receivable [Member]	Dec. 31, 2013 Customer Two[Member] Accounts Receivable [Member]	Sep. 30, 2014 Customer Three [Member] Accounts Receivable [Member]
Concentration Risk [Line Items]
Percentage of concentration of credit risk	35.00%	36.00%	17.00%	15.00%	88.00%	88.00%	11.00%	39.00%	14.00%	14.00%	10.00%	10.00%