Stock-based Compensation (Details) $ / shares in Units, $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
	May. 07, 2014 shares	Jun. 30, 2015 USD ($) $ / shares shares	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) item $ / shares shares	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($) $ / shares shares
Stock-based Compensation
Stock-based compensation expense		$ 4,600	$ 4,900	$ 7,700	$ 8,300
Equity Incentive Plan 2010
Stock-based Compensation
Shares included in the authorized shares which was previously reserved for issuance | shares		1,648,524		1,648,524
Shares
Granted (in shares) | shares	0
Equity Incentive Plan 2014
Stock-based Compensation
Number of shares authorized | shares		6,648,524		6,648,524
Employee and Directors Stock Options
Stock-based Compensation
Term of award				10 years
Vesting period				3 years
Stock-based compensation expense		$ 0	0	$ 0	0
Unrecognized compensation cost		$ 0		$ 0
Shares
Balance at the beginning of the period (in shares) | shares				3,312,158
Exercised (in shares) | shares				(2,000)
Balance at the end of the period (in shares) | shares		3,310,158		3,310,158		3,312,158
Vested and exercisable at the end of the period (in shares) | shares		3,310,158		3,310,158
Exercise Price
Balance at the beginning of the period (in dollars per share) | $ / shares				$ 20.40
Exercised (in dollars per share) | $ / shares				20.00
Balance at the end of the period (in dollars per share) | $ / shares		$ 20.40		20.40		$ 20.40
Vested and exercisable at the end of the period (in dollars per share) | $ / shares		$ 20.40		$ 20.40
Remaining Contractual Term
SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2				4 years 11 months 27 days		5 years 5 months 27 days
SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2				4 years 11 months 27 days		5 years 5 months 27 days
Vested and exercisable at the end of the period				4 years 11 months 27 days
Aggregate Intrinsic Value
Balance at the beginning of the period				$ 46,077
Exercised				35
Balance at the end of the period		$ 44,691		44,691		$ 46,077
Vested and exercisable at the end of the period		44,691		$ 44,691
Restricted Stock Units
Stock-based Compensation
Vesting period				3 years
Number of different vesting criteria | item				3
Stock-based compensation expense		4,600	$ 4,900	$ 7,700	$ 8,300
Unrecognized compensation cost		$ 23,600		$ 23,600
Restricted Stock With Book Value Conditions
Stock-based Compensation
Vesting period				3 years
Restricted Stock With Total Shareholder Return Conditions
Stock-based Compensation
Vesting period				3 years
Restricted Stock With Total Shareholder Return Conditions | Minimum
Stock-based Compensation
Percentage of shares vested				0.00%
Restricted Stock With Total Shareholder Return Conditions | Maximum
Stock-based Compensation
Percentage of shares vested				200.00%