Shareholders’ Equity (Narrative) (Details) $ / shares in Units, $ in Thousands		1 Months Ended					3 Months Ended		6 Months Ended		9 Months Ended	12 Months Ended
	Jan. 25, 2014 USD ($) shares	Apr. 30, 2015 shares	Feb. 28, 2015 shares	Dec. 31, 2014 USD ($) party $ / shares shares	Jul. 31, 2014 USD ($) $ / shares shares	Sep. 30, 2013	Jun. 30, 2015 USD ($) $ / shares shares	Jun. 30, 2014 USD ($) $ / shares	Jun. 30, 2015 USD ($) $ / shares shares	Jun. 30, 2014 USD ($) $ / shares	Sep. 30, 2013 shares	Dec. 31, 2014 USD ($) $ / shares shares	Jul. 31, 2015 shares	Aug. 31, 2014 shares	Jan. 02, 2014 shares	Dec. 31, 2013 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares authorized				100,000,000	12,000,000,000		100,000,000		100,000,000			100,000,000		100,000,000
Preferred stock, shares authorized							8,000,000		8,000,000
Preferred stock, par value | $ / shares							$ 0.0001		$ 0.0001
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares							$ 18.79	$ 10.73	$ 18.87	$ 9.95
Unamortized share-based compensation expense | $							$ 14,822		$ 14,822
Recognized weighted average period									3 years 3 months 4 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period									7,500			0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value | $									$ 111
Warrants Granted To Purchase Common Stock				51,000
Warrants Issued, Number of Third Party Recipients | party				2
Third party share-based compensation expense | $							218		416
Share-based compensation expense | $							3,880	$ 2,154	$ 7,282	$ 4,852
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period									0
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period									7,500
Research and development [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense | $							1,162	182	$ 2,210	549
General and administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense | $							2,718	1,972	5,072	4,303
Stock Option [Member] | Research and development [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense | $							413	36	972	44
Stock Option [Member] | General and administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense | $							$ 918	266	$ 1,507	289
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number				1,279,007			1,108,281		1,108,281			1,279,007				1,746,853
Restricted Stock [Member] | Research and development [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized weighted average period									7 months
Share-based compensation expense | $							$ 735	146	$ 1,213	505
Unamortized share-based compensation expense | $							325		$ 325
Restricted Stock [Member] | General and administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized weighted average period									21 months
Share-based compensation expense | $							1,596	$ 1,706	$ 3,174	$ 4,014
Unamortized share-based compensation expense | $							$ 3,661		$ 3,661
Series C-1 Preferred Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock, shares authorized				11,000			11,000		11,000			11,000
Preferred stock, par value | $ / shares				$ 0.0001			$ 0.0001		$ 0.0001			$ 0.0001
Shares issued upon conversion, per share							1,724		1,724
Preferred stock, shares issued				3,917			3,917		3,917			3,917
Shares reserved for future issuance							6,752,908		6,752,908
Liquidation preference per share | $ / shares				$ 1,000								$ 1,000
Liquidation preference | $				$ 3,917								$ 3,917
Series C-1 Preferred Stock [Member] | Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock issued												5,341,670
Series F Preferred Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock, shares authorized				10,000			10,000		10,000			10,000
Preferred stock, par value | $ / shares				$ 0.0001			$ 0.0001		$ 0.0001			$ 0.0001
Shares issued upon conversion, per share							286		286
Preferred stock, shares issued				2,798			2,737		2,737			2,798
Shares reserved for future issuance							782,032		782,032
Liquidation preference | $				$ 2,737								$ 2,737
Series F Preferred Stock [Member] | Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock issued									17,360			129,105
Consultant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of share-based payment awards									3 years
Stock options granted									60,000
Share-based compensation expense | $							$ 64		$ 362
Consultant [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock issued	2,976
Stock Issued During Period, Value, New Issues | $	$ 25
Director [Member] | Common Stock [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock issued											79,622
Chief Executive Officer [Member] | Restricted Stock [Member] | Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number													1,042,680
Chief Executive Officer [Member] | Common Stock [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock issued											1,327,048
Employees [Member] | Common Stock [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock issued											336,185
2013 Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity plan, term						10 years
Period of share-based payment awards						4 years
Automatic annual increase based on outstanding shares of Common Stock as of the last day of the previous year end, percent						10.00%
Shares available for grant							171,089		171,089					1,100,000	440,441
Common Stock, Capital Shares Reserved for Future Issuance							1,089,524		1,089,524
2013 Equity Plan [Member] | Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of share-based payment awards						3 years
2013 Equity Plan [Member] | Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted			300,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Approval Period			1 year
2013 Equity Plan [Member] | Chief Financial Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted		60,000
One-year Anniversary Date of Grant [Member] | 2013 Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage						25.00%
One-year Anniversary Date of Grant [Member] | 2013 Equity Plan [Member] | Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage						33.00%
One-year Anniversary Date of Grant [Member] | 2013 Equity Plan [Member] | Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage			25.00%
One-year Anniversary Date of Grant [Member] | 2013 Equity Plan [Member] | Chief Financial Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage		25.00%
Upon Grant [Member] | Consultant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage									25.00%
Underwriting Agreement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock to be issued and sold in underwriting agreement					5,395,000
Proceeds from the underwriting agreement, including additional shares sold, gross | $					$ 56,600
Proceeds from the underwriting agreement, including additional shares sold, net of cost | $					53,100
Issuance costs | $					$ 3,500
IPO [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price per share of shares sold (usd per share) | $ / shares					$ 10.50
Grant One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Class of Warrant or Right, Award Vesting Period				4 years
Grant One [Member] | One-year Anniversary Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Class of Warrant or Right, Award Vesting Rights, Percentage				25.00%
Grant Two [Member] | One-year Anniversary Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Class of Warrant or Right, Award Vesting Rights, Percentage				100.00%