XML 13 R54.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Commitments and Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 3 Months Ended
--- | ---
Mar. 31, 2015
Loss Contingencies [Line Items] |
Period of time to achieve earnings and cash building targets | 6 months
Accrued bonus liability | $ 11.0 us-gaap_DeferredCompensationArrangementWithIndividualRecordedLiability
Total estimated expense | $ 5.5 us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense

X
- Definition Deferred Compensation Arrangement with Individual, Minimum Period Financial Metrics Must Be Met + References No definition available. + Details
Name: | nvtl_DeferredCompensationArrangementwithIndividualMinimumPeriodFinancialMetricsMustBeMet
Namespace Prefix: | nvtl_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The compensation expense recognized during the period pertaining to the deferred compensation arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 710 -SubTopic 10 -Section 30 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363 + Details
Name: | us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 710 -SubTopic 10 -Section 30 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363 + Details
Name: | us-gaap_DeferredCompensationArrangementWithIndividualRecordedLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_LossContingenciesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration