Equity - Narrative (Details)		12 Months Ended
	Nov. 18, 2015 $ / shares shares	Dec. 31, 2016 USD ($) plan $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	May 12, 2014 USD ($)
Class of Stock [Line Items]
Number of share-based compensation plans | plan		4
Intrinsic value of options exercised		$ 6,460,000	$ 17,181,000	$ 10,566,000
Intrinsic value of options vested		7,378,000	$ 10,044,000	$ 6,615,000
Total unrecognized compensation expense		$ 1,064,000
Weighted-average grant date fair value for options granted during the period (in dollars per share) | $ / shares		$ 0.00	$ 5.15	$ 4.18
Shares issued for services performed (in shares) | shares		43,344	16,493	15,958
Shares issued for services performed		$ 346,000	$ 164,000	$ 117,000
Authorized share amount for repurchase		$ 66,000,000	$ 60,000,000	$ 20,000,000	$ 10,000,000
Stock repurchase (in shares) | shares		1,338,616
Shares repurchased, value		$ 10,338,000
Commissions		40,000
Remaining authorizations under the repurchase program, amount		$ 9,936,000
Warrants
Class of Stock [Line Items]
Warrants outstanding (in shares) | shares	42,400
Warrants outstanding (in dollars per share) | $ / shares	$ 1.09
Warrants term	5 years
Common Stock
Class of Stock [Line Items]
Shares issued for services performed (in shares) | shares			11,321	15,958
Consultant | Common Stock
Class of Stock [Line Items]
Shares issued for services performed (in shares) | shares		43,344
Shares issued for services performed		$ 345,700
Restricted Stock
Class of Stock [Line Items]
Total unrecognized stock-based compensation related to time-based, nonvested restricted stock		$ 21,905,000
Expenses expected to be recognized over a weighted-average period		1 year 10 months 24 days
Restricted Stock | Minimum
Class of Stock [Line Items]
Vesting period		1 year
Restricted Stock | Maximum
Class of Stock [Line Items]
Vesting period		3 years