Equity Equity, Textuals (Details) (USD $)	0 Months Ended	3 Months Ended	6 Months Ended
May 09, 2013	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Dividends declared per share	$ 0.07	$ 0.07	$ 0.06	$ 0.13	$ 0.11
Dividends, Common Stock, Cash				$ 14,800,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount				190,100,000
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Purchase of Interest by Parent				0.10
Payments to Acquire Additional Interest in Subsidiaries				$ 8,333,000	$ 0
Sale of Stock, Percentage of Ownership before Transaction				70.00%
Sale of Stock, Percentage of Ownership after Transaction				80.00%

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

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

Represents the purchase by the parent of an additional equity interest in a subsidiary during the period, thereby effecting a change in total (consolidated) equity attributable to the parent. The purchase of the additional equity interest represented by this element increases the parent's controlling interest in the subsidiary.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=18733093&loc=SL4573702-111684

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 55

-Paragraph 4M

-URI http://asc.fasb.org/extlink&oid=31814832&loc=SL4591554-111686

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

+ References

+ Details

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

- Definition

The cash outflow associated with the purchase of noncontrolling interest during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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

- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company before stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Amount remaining of a stock repurchase plan authorized by an entity's Board of Directors.

+ References

No definition available.

+ Details

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