Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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-Section S99
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-Subparagraph (SX 210.4-08.(k)(1))
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 850
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-Section 50
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Expenditures for salaries of officers. Does not include allocated share-based compensation, pension and post-retirement benefit expense or other labor-related non-salary expense. For commercial and industrial companies, excludes any direct and overhead labor that is included in cost of goods sold.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
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Stock-Based Compensation Stock-Based Compensation - Repurchase of Subsidiary Units (Details) - Founder and President - Repurchase of Subsidiary Units, February 2011 - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Officers' compensation	$ (0.1)	$ 0.2	$ 0.1	$ 0.3
Accounts Payable, Accrued Expenses and Other Current Liabilities
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Due to related parties, current	2.6		2.6		$ 2.5
Other Liabilities
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Due to related parties, noncurrent	$ 0.3		$ 0.3		$ 0.3