Long Term Debt (Parenthetical) (Detail)	12 Months Ended
Dec. 31, 2015
1.85% to 3.80%, due 2016 to 2045
Debt Instrument [Line Items]
Interest Rate, minimum	1.85%
Interest Rate, maximum	3.80%
1.85% to 3.80%, due 2016 to 2045 \| Minimum
Debt Instrument [Line Items]
Long-term debt maturity year	2016
1.85% to 3.80%, due 2016 to 2045 \| Maximum
Debt Instrument [Line Items]
Long-term debt maturity year	2045
4.07% to 5.72%, due 2019 to 2046
Debt Instrument [Line Items]
Interest Rate, minimum	4.07%
Interest Rate, maximum	5.72%
4.07% to 5.72%, due 2019 to 2046 \| Minimum
Debt Instrument [Line Items]
Long-term debt maturity year	2019
4.07% to 5.72%, due 2019 to 2046 \| Maximum
Debt Instrument [Line Items]
Long-term debt maturity year	2046
6.15% to 9.13%, due 2016 to 2036
Debt Instrument [Line Items]
Interest Rate, minimum	6.15%
Interest Rate, maximum	9.13%
6.15% to 9.13%, due 2016 to 2036 \| Minimum
Debt Instrument [Line Items]
Long-term debt maturity year	2016
6.15% to 9.13%, due 2016 to 2036 \| Maximum
Debt Instrument [Line Items]
Long-term debt maturity year	2036

Year the debt instrument matures.

No definition available.

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- Definition

Maximum contractual interest rate for funds borrowed, under the debt agreement.

+ 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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Minimum contractual interest rate for funds borrowed, under the debt agreement.

+ 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 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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