Aggregate dividends paid during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Name:	us-gaap_CommonStockDividendsPerShareCashPaid
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

Basis of Presentation and Significant Accounting Policies - Summary of Characterization of Dividend Distributions for Federal Income Tax Purposes (Parenthetical) (Details) - $ / shares				1 Months Ended	12 Months Ended
	Jan. 12, 2018	Jan. 13, 2017	Jan. 15, 2016	Dec. 31, 2014	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Line Items]
Cash dividend		$ 0.095	$ 0.095	$ 0.039	$ 0.380	$ 0.380	$ 0.324
Subsequent Event [Member]
Income Taxes [Line Items]
Cash dividend	$ 0.095