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Preferred Stocks (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Class of Stock [Line Items] |  |  |
Preferred stocks | $ 15,000 | $ 15,000 |
Preferred stock redemption price upon liquidation (in dollars per share) | $ 100 |  |
Cumulative Preferred Stock, Par Value $100 Issuable in Series [Member] |  |  |
Class of Stock [Line Items] |  |  |
Authorized preferred cumulative shares (in shares) | 500,000 | 500,000 |
Cumulative preferred shares, par value (in dollars per share) | $ 100.00 | $ 100.00 |
Preferred stock, series 4.50% [Member] |  |  |
Class of Stock [Line Items] |  |  |
Preferred stocks | $ 10,000 | $ 10,000 |
Preferred shares outstanding (in shares) | 100,000 | 100,000 |
Preferred stock, $100 par value | 4.50% | 4.50% | 4.50%
Preferred stock, dividends per share, declared | $ 4.50 | $ 4.50 | $ 4.50
Preferred stock, redemption per share amount | $ 105 |  |
Preferred stock, series 4.70% [Member] |  |  |
Class of Stock [Line Items] |  |  |
Preferred stocks | $ 5,000 | $ 5,000 |
Preferred shares outstanding (in shares) | 50,000 | 50,000 |
Preferred stock, $100 par value | 4.70% | 4.70% | 4.70%
Preferred stock, dividends per share, declared | $ 4.70 | $ 4.70 | $ 4.70
Preferred stock, redemption per share amount | $ 102 |  |
Cumulative preferred stock A, without par value, issuable in series [Member] |  |  |
Class of Stock [Line Items] |  |  |
Authorized preferred cumulative shares (in shares) | 1,000,000 | 1,000,000 |
Cumulative preference stock , without par value, issuable in series [Member] |  |  |
Class of Stock [Line Items] |  |  |
Authorized preferred cumulative shares (in shares) | 500,000 | 500,000 |

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- Definition Aggregate dividends declared during the period for each share of preferred stock outstanding. + References No definition available. + Details
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- Definition The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21484-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(d)(1)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(d)(1)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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- Definition The price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21564-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21488-112644 + Details
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- Definition The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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