Stock-Based Compensation Stock-based Compensation Expense (Details) $ in Thousands	Dec. 31, 2016 USD ($)
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
2017	$ 1,912
2018	1,440
2019	405
2020	56
Total	$ 3,813

Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options, Year Four

No definition available.

Name:	buff_EmployeeServiceSharebasedCompensationNonvestedAwardsCompensationNotyetRecognizedStockOptionsYearFour
Namespace Prefix:	buff_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options, Year One

No definition available.

Name:	buff_EmployeeServiceSharebasedCompensationNonvestedAwardsCompensationNotyetRecognizedStockOptionsYearOne
Namespace Prefix:	buff_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options, Year Three

No definition available.

Name:	buff_EmployeeServiceSharebasedCompensationNonvestedAwardsCompensationNotyetRecognizedStockOptionsYearThree
Namespace Prefix:	buff_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options, Year Two

No definition available.

Name:	buff_EmployeeServiceSharebasedCompensationNonvestedAwardsCompensationNotyetRecognizedStockOptionsYearTwo
Namespace Prefix:	buff_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

No definition available.

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

Unrecognized cost of unvested options awarded to employees as compensation.

No definition available.

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