Share-Based Compensation - Summary of Nonvested Restricted Stock 2 (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value per share on valuation date		$ 78.55
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period		0	213
Fair value per share on valuation date	$ 0.00	$ 0.00	$ 51.35
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period		24,264	25,899
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 1,527	$ 1,725	$ 1,323
Nonvested Restricted Stock Units R S U [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period	0
Vested Restricted Stock Units R S U [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period	24,262

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

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