Consolidated Consolidated Statements of Cash Flows (Parenthetical) $ in Millions	9 Months Ended
Sep. 30, 2019 USD ($)
2018 Underwritten Public Offering
Subsidiary Sale Of Stock [Line Items]
Underwriting discounts, commissions and costs	$ 2.6
2019 Underwritten Public and Private Offerings
Subsidiary Sale Of Stock [Line Items]
Underwriting discounts, commissions and costs	$ 1.7

Expense related to distribution, servicing and underwriting fees.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.14)
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration