The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

Name:	us-gaap_RepaymentsOfSeniorDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Subsequent Events (Details) - USD ($) $ in Millions		12 Months Ended
Subsequent Events (Details) - USD ($) $ in Millions	Jan. 17, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Subsequent Event [Line Items]
Repayments of senior notes		$ 148.2	$ 0.0	$ 0.0
2021 Senior Notes [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Repayments of senior notes	$ 151.8