Bank segment - Contingencies (Details) - USD ($) $ in Millions	1 Months Ended
Dec. 31, 2014	Jun. 30, 2015
March 2011 Class Action Lawsuit
Loss Contingencies [Line Items]
Litigation Settlement, Amount	$ 2.0
Loss Contingency Accrual		$ 2.0
American Savings Bank (ASB)
Loss Contingencies [Line Items]
Unfunded commitments to fund the company's LIHTC	$ 14.8	$ 8.6

Amount of loss contingency liability.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Name:	us-gaap_LossContingencyAccrualAtCarryingValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant