SHAREHOLDER'S EQUITY SHAREHOLDERS' EQUITY, SUBSEQUENT EVENT (Details) (USD $)	1 Months Ended	3 Months Ended	12 Months Ended
Feb. 24, 2015	Feb. 13, 2014	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Subsequent Event [Line Items]
Common Stock, Dividends, Per Share, Declared		$ 0.20	$ 0.125	$ 0.50	$ 0.20	$ 0.00
DividendIncrease	60.00%alk_DividendIncrease

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: 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_CommonStockDividendsPerShareDeclared
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration