Summary of Significant Accounting Policies - Newly Issued, but not yet Effective Accounting Standards (Details) $ in Millions	Jan. 01, 2019 USD ($)
Forecast \| ASU No 2016-02, Leases (Topic 842)
Increase in assets and liabilities	$ 9.6

Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22580-107794

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