Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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-Name Accounting Standards Codification
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Percentage of vesting of share-based compensation awards.

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Equity-Based Compensation - Profits Interests Plans (Details) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2014	Dec. 31, 2018
BKLS LLC Profit Interests Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)		3 years
Grants in period, weighted average grant date fair value (in dollars per share)	$ 2.10
BKLS LLC Profit Interests Plan \| Vesting after second year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		50.00%
BKLS LLC Profit Interests Plan \| Vesting after third year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		50.00%
BKLS LLC Profit Interests Plan \| Common Class B
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized			11,111,111
ServiceLink Profits Interests
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend rate (as a percent)	0.00%