The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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

Subsequent Events (Details) - 2017 Long-Term Incentive Plan - shares	Feb. 02, 2018	Dec. 31, 2017	Feb. 16, 2017
Subsequent Event [Line Items]
Number of shares authorized (in shares)		1,000,000	1,125,000
Subsequent Event
Subsequent Event [Line Items]
Number of additional shares authorized (in shares)	425,000
Number of shares authorized (in shares)	1,550,000