The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
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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.

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- Definition

Number of non-option equity instruments exercised by participants.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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-Publisher FASB
-Name Accounting Standards Codification
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Per share or per unit amount of equity securities issued.

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Employee Share-Based Incentive Compensation Plans WTM Stock options (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Share-based compensation arrangement by share-based payment award
Shares Issued, Price Per Share			$ 742
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements		882
Employee Stock Option [Member]
Share-based compensation arrangement by share-based payment award
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements		125,000
Common Stock [Member]
Share-based compensation arrangement by share-based payment award
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	5,142
Chief Executive Officer \| Employee Stock Option [Member]
Share-based compensation arrangement by share-based payment award
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 4,400,000
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised	125,000
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	40,000
Combination Two \| Employee Stock Option [Member]
Share-based compensation arrangement by share-based payment award
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value			$ 8,400,000
Conversion of Stock, Shares Converted			9,930
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements			80,000
Combination One \| Employee Stock Option [Member]
Share-based compensation arrangement by share-based payment award
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value			$ 400,000
Shares Issued, Price Per Share			$ 742
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements			5,000