Increase in common stock capital shares reserved for future issuance.

No definition available.

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- Definition

The maximum annual increase in the number of shares reserved under the plan as a proportion of outstanding common stock.

+ References

No definition available.

+ Details

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Namespace Prefix:	agle_
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- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
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+ Details

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- Definition

Date the equity-based award expires, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Number of new stock issued during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-Name Accounting Standards Codification
-Topic 505
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=agle_TwentySixteenEquityIncentivePlanMember
Namespace Prefix:
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Subsequent Events - Additional Information (Details) - USD ($) $ in Millions		1 Months Ended	9 Months Ended
	Oct. 08, 2018	Oct. 31, 2018	Sep. 30, 2018
Subsequent Event \| JonesTrading Institutional Services LLC \| At-the-Market (ATM) Sales Agreement
Subsequent Event [Line Items]
Common stock shares sold		1,845,820
Net proceeds from sale of common stock		$ 16.4
2016 Equity Incentive Plan
Subsequent Event [Line Items]
Percentage of outstanding share of common stock			4.00%
2016 Equity Incentive Plan \| Subsequent Event
Subsequent Event [Line Items]
Increase in number of shares of common stock reserved for issuance	1,759,602
Share based compensation plan expiration date	Aug. 07, 2028
Percentage of outstanding share of common stock	4.00%