Derivatives - Additional Information (Details) - Interest Rate Cash Flow Hedges - Variable-rate Debt - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Derivative [Line Items]
Amount of hedged debt	$ 14.1	$ 15.5
Hedged debt as a percent of total debt (percent)	2.50%	2.70%

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.

No definition available.

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