Special Dividend - Additional Information (Details) $ / shares in Units, $ in Millions	Mar. 09, 2017 USD ($) $ / shares
Equity [Abstract]
Cash dividend (in dollars per share) \| $ / shares	$ 3.00
Cash dividend, subordinated debentures (in dollars per share) \| $ / shares	$ 5.00
Interest rate of subordinated debentures	6.00%
Decrease in stockholders' equity	$ 458.7
Increase in long-term debt	284.5
Decrease in cash	$ 174.2

Amount of paid and unpaid paid-in-kind dividends (PIK) in debentures.

No definition available.

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- Definition

The increase (decrease) in long term debt during the period.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in cash. Cash is the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Includes effect from exchange rate changes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 230
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49171198&loc=d3e33268-110906

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

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- References

No definition available.

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- Definition

The increase (decrease) in stockholders' equity during the period.

+ References

Reference 1: 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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- Definition

Stated interest rate of the subordinated debt.

+ References

No definition available.

+ Details

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