Cumulative Share Equivalents Issued From The Plan

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Performance Units Payout Percentage

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- Definition

Potential Number Of Shares Issued At Vesting Of Performance Units

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercised, Intrinsic Value

+ References

No definition available.

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- Definition

Share equivalent ratio, other than stock options and SARs

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No definition available.

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- Definition

Stocks Issued During Period Value Restricted Stock Award Gross.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

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- Definition

Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited 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)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ 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)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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).

+ 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)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ 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 (a)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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

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- Definition

Net number of share options (or share units) granted during the 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)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

+ Details

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- Definition

Number of shares for which recognition of compensation cost was accelerated.

+ References

No definition available.

+ Details

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12. Equity Compensation Plan Narrative (Details) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2017 shares	Dec. 31, 2016 USD ($) $ / shares Rate shares	Dec. 31, 2015 USD ($) $ / shares Rate shares	Dec. 31, 2014 USD ($) $ / shares shares
Equity Compensation Plan [Line Items]
Maximum Number of Share Equivalents Authorized		6,300,000
Share equivalent ratio, other than stock options and SARs		2.36
Cumulative Share Equivalents Issued From The Plan		3,913,287
Share Equivalents Remaining Available		2,386,713
Shares of restricted stock, Granted		175,410	171,475	149,608
Value of Restricted Stock Awarded during period \| $		$ 6.0	$ 5.5	$ 3.8
Shares of restricted stock, Vested		167,419	138,585	125,798
Value of Restricted Stock on Vesting Date \| $		$ 6.2	$ 4.3	$ 3.4
Unearned Compensation on Restricted Stock \| $		$ 6.4
Weighted Average Vesting Period		1 year 37 days
Granted		0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercised, Intrinsic Value \| $		$ 5.2	$ 3.7	$ 7.7
Performance units, forfeited		47,958	7,737	3,785
Weighted Average Grant Date Fair Value, Forfeited \| $ / shares		$ 30.41	$ 28.71	$ 23.98
Stock Options [Member]
Equity Compensation Plan [Line Items]
Weighted Average Vesting Period		1 day	73 days	183 days
Performance Shares [Member]
Equity Compensation Plan [Line Items]
Shares of restricted stock, Granted		112,951	48,674	110,441
Unearned Compensation on Restricted Stock \| $		$ 3.7
Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number			320,676
Share-based Compensation Arrangement by Share-based Payment Award Accelerated Compensation Cost \| $			$ 1.9
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period	57,177
Performance units, forfeited		0	4,225	0
Weighted Average Grant Date Fair Value, Forfeited \| $ / shares			$ 36.30
Minimum [Member]
Equity Compensation Plan [Line Items]
Potential Number Of Shares Issued At Vesting Of Performance Units		0.00%
Maximum [Member]
Equity Compensation Plan [Line Items]
Performance Units Payout Percentage		150.00%
Potential Number Of Shares Issued At Vesting Of Performance Units			300.00%
Performance Units Granted 2/23/2012 [Member] \| Performance Shares [Member]
Equity Compensation Plan [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period			0
Performance Units Payout Percentage \| Rate		0.00%
Performance Units Granted 2/21/2013 [Member] \| Performance Shares [Member]
Equity Compensation Plan [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period		32,985
Share-based Compensation Award, 300% payout [Member] \| Performance Units Granted 2/21/2013 [Member] \| Performance Shares [Member]
Equity Compensation Plan [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period			115,437
Share-based Compensation Award, 300% payout [Member] \| Performance Units Granted 2/21/2014 [Member] \| Performance Shares [Member]
Equity Compensation Plan [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period			205,240
Performance Units Payout Percentage \| Rate			300.00%
Share-based Compensation Award, 100% payout [Member] \| Performance Units Granted 2/21/2014 [Member] \| Performance Shares [Member]
Equity Compensation Plan [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period			2,125
Performance Units Payout Percentage \| Rate			100.00%