XML 52 R39.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Nature of Operations and Summary of Significant Accounting Policies - Capitalized Interest (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Capitalized Interest |  |  |
Capitalized interest costs | $ 1.5 | $ 1.4 | $ 1.5

X
- Definition Amount of interest capitalized, including amount of allowance for funds used during construction. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 835 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6501662&loc=d3e56162-110433 + Details
Name: | us-gaap_InterestCostsIncurredCapitalized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_InterestCostsIncurredCapitalizedAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration