Income taxes: (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Income taxes
NOLs	$ 76,411
Minimum Alternative Tax Credits
Income taxes
Tax Credits	1,478
2018
Income taxes
NOLs	61,533
2019
Income taxes
NOLs	10,516
2020
Income taxes
NOLs	4,362
None \| Minimum Alternative Tax Credits
Income taxes
Tax Credits	$ 1,478

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Carryforwards

-URI http://asc.fasb.org/extlink&oid=6506874

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant