SCHEDULE II - CONDENSED FINANCIAL INFORMATION OF REGISTRANT (Details) - shares	Dec. 31, 2017	Dec. 31, 2016
Stockholders' Equity Parenthetical Information
Preferred stock - shares authorized (in shares)	10,000,000	10,000,000
Common stock - shares authorized (in shares)	800,000,000	800,000,000

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_PreferredStockSharesAuthorized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant