Percentage of financial targets to be achieved for participants to receive award.

No definition available.

Name:	acta_PercentageOfFinancialTargetsToBeAchievedForParticipantsToReceiveAward
Namespace Prefix:	acta_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Number of Employees

+ References

No definition available.

+ Details

Name:	acta_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsGrantsinPeriodNumberofEmployees
Namespace Prefix:	acta_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_AllocatedShareBasedCompensationExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=acta_PerformanceMetricsOfGovDeliveryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=acta_VestingInFirstQuarterTwentyFifteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=acta_VestingInFirstQuarterTwentySixteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=acta_PerformanceBasedPlanTwoThousandFourteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=acta_PerformanceBasedPlanTwoThousandFifteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=acta_PerformanceBasedPlanTwoThousandSixteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=acta_ConditionOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=acta_ConditionTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TitleOfIndividualAxis=us-gaap_ExecutiveOfficerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=acta_PerformanceBasedPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Equity-Based Compensation - Restricted Stock Awards with Performance Conditions Additional Information (Detail) $ / shares in Units, $ in Thousands				3 Months Ended			12 Months Ended
	Mar. 03, 2016 $ / shares	Feb. 27, 2015 $ / shares	Feb. 28, 2014 $ / shares	Mar. 31, 2016 USD ($) $ / shares shares	Mar. 31, 2015 USD ($) $ / shares shares	Mar. 31, 2014 shares	Dec. 31, 2015 shares	Dec. 31, 2014 employee shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized equity-based compensation \| $				$ 28,983	$ 42,705
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, granted (in shares)				434,283	441,256
Number of shares, vested				657,317	644,247
Number of shares, forfeited (in shares)				588,819	43,660
Weighted average fair value, vested (in dollars per share) \| $ / shares				$ 18.75	$ 19.70
Performance Metrics Of Gov Delivery \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, granted (in shares)								244,506
Number of employees granted shares in period \| employee								2
Number of shares, vested				81,322	56,587
Number of shares, forfeited (in shares)				62,937	43,660
Performance Metrics Of Gov Delivery \| Restricted Stock \| Vesting In First Quarter Twenty Fifteen
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, granted (in shares)								100,247
Performance Metrics Of Gov Delivery \| Restricted Stock \| Vesting In First Quarter Twenty Sixteen
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, granted (in shares)								144,259
Performance Based Plan Two Thousand Fourteen \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, granted (in shares)						158,942
Weighted average fair value, vested (in dollars per share) \| $ / shares			$ 20.33
Performance Based Plan Two Thousand Fifteen \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, granted (in shares)					316,715
Weighted average fair value, vested (in dollars per share) \| $ / shares	$ 8.44	$ 16.76
Performance Based Plan Two Thousand Sixteen \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, granted (in shares)				419,283
Share based compensation expense \| $				$ 1,000	$ 1,400
Unrecognized equity-based compensation \| $				$ 2,700
Condition One \| Performance Based Plan Two Thousand Fourteen \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of financial targets to be achieved for participants to receive award						100.00%
Condition One \| Performance Based Plan Two Thousand Fifteen \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of financial targets to be achieved for participants to receive award					150.00%
Condition One \| Performance Based Plan Two Thousand Sixteen \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of financial targets to be achieved for participants to receive award				100.00%
Condition Two \| Performance Based Plan Two Thousand Fourteen \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of financial targets to be achieved for participants to receive award						100.00%
Condition Two \| Performance Based Plan Two Thousand Fourteen \| Restricted Stock \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of financial targets to be achieved for participants to receive award						0.00%
Condition Two \| Performance Based Plan Two Thousand Fourteen \| Restricted Stock \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of financial targets to be achieved for participants to receive award						100.00%
Condition Two \| Performance Based Plan Two Thousand Fifteen \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of financial targets to be achieved for participants to receive award					150.00%
Condition Two \| Performance Based Plan Two Thousand Fifteen \| Restricted Stock \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of financial targets to be achieved for participants to receive award					0.00%
Condition Two \| Performance Based Plan Two Thousand Fifteen \| Restricted Stock \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of financial targets to be achieved for participants to receive award					150.00%
Condition Two \| Performance Based Plan Two Thousand Sixteen \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of financial targets to be achieved for participants to receive award				100.00%
Condition Two \| Performance Based Plan Two Thousand Sixteen \| Restricted Stock \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of financial targets to be achieved for participants to receive award				0.00%
Condition Two \| Performance Based Plan Two Thousand Sixteen \| Restricted Stock \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of financial targets to be achieved for participants to receive award				100.00%
Executives \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, granted (in shares)					20,000
Number of shares, vested				5,000
Executives \| Performance Based Plan \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, granted (in shares)							42,341
Number of shares, vested				28,341
Number of shares, forfeited (in shares)				14,000