Income Taxes - Other Tax Matters (Details) - Internal Revenue Service (IRS) [Member]	12 Months Ended
Dec. 31, 2016 USD ($)
Tax Year 2011
Income Tax Examination [Line Items]
Increase (decrease) to shareholders' net income resulting from IRS examination
Tax Year 2012
Income Tax Examination [Line Items]
Increase (decrease) to shareholders' net income resulting from IRS examination

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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Balance Type:	na
Period Type:	duration