Debt, Non-Bank Debt (Details) (Senior Notes [Member], USD $)	6 Months Ended
Jun. 30, 2014 Senior Notes Due In 2014 [Member]	Jun. 30, 2013 Senior Notes Due In June 2013 [Member]	Jun. 30, 2013 Senior Notes Due In January 2013 [Member]
Non-Bank Debt (Textual)
Debt repayments	$ 200,000,000	$ 300,000,000	$ 180,000,000
Interest rate of notes in percentage	4.75%	4.75%	6.70%

The cash outflow attributable to repayments of borrowings not otherwise defined in the taxonomy (with maturities initially due after one year or beyond the operating cycle if longer).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Name:	us-gaap_RepaymentsOfOtherLongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration