Summary of Significant Accounting Policies - Reclassifications (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other assets		$ 0
Net cash used in investing activities	$ (42,367)	(42,854)
Net change in cash, cash equivalents and restricted cash		(968)
Cash, cash equivalents and restricted cash - beginning of period	118,560	25,045
Cash, cash equivalents and restricted cash - end of period	$ 68,938	24,077
As Previously Reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other assets		5,771
Net cash used in investing activities		(37,083)
Net change in cash, cash equivalents and restricted cash		4,803
Cash, cash equivalents and restricted cash - beginning of period		11,231
Cash, cash equivalents and restricted cash - end of period		$ 16,034

Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3521-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=98513485&loc=SL98516268-108586

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 4
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 230
-Section 45
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